UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                          ----------------------------

                                  SCHEDULE 13D
                    Under the Securities Exchange Act of 1934
                                (Amendment No. 1)

                             Inter-Tel, Incorporated
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                                (Name of Issuer)

                                  Common Stock
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                         (Title of Class of Securities)

                                    458372109
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                                 (CUSIP Number)

                                Steven G. Mihaylo
                           P.O. Box 19790 Reno, Nevada
                                      89511
                                 (775) 338-4699
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           (Name, Address and Telephone Number of Person Authorized to
                       Receive Notices and Communications)

                                   Copies to:
                             Brian J. McCarthy, Esq.
                    Skadden, Arps, Slate, Meagher & Flom LLP
                             300 South Grand Avenue
                          Los Angeles, California 90071
                                 (213) 687-5000

                                 April 10, 2006
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             (Date of Event Which Requires Filing of This Statement)


If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box
[   ].

Note: Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See ss.240.13d-7 for other
parties to whom copies are to be sent.

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).






CUSIP No. 458372 109
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1.      Names of Reporting Persons. Steven G. Mihaylo

        I.R.S. Identification Nos. of above persons (entities only). Not
        applicable.

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2.      Check the Appropriate Box if a Member of a Group (see Instructions)

                      (A) [___]
                      (B) [___]
           Not applicable.

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3.      SEC Use Only

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4.      Source of Funds (see Instructions)

        Not applicable.

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5.      Check if Disclosure of Legal Proceedings Is Required Pursuant to
        Items 2(d) or 2(e) [__]

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6.      Citizenship or Place of Organization

        Nevada
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Number of Shares          7.       Sole Voting Power
Beneficially Owned by
Each Reporting Person              5,179,498
With
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                          8.       Shared Voting Power

                                   None
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                          9.       Sole Dispositive Power

                                   5,179,498
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                          10.      Shared Dispositive Power

                                   None
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11.     Aggregate Amount Beneficially Owned by Each Reporting Person

        5,179,498

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12.     Check if the Aggregate Amount In Row (11) Excludes Certain Shares (See
        Instructions) [__]

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13.     Percent of Class Represented by Amount in Row 11

        19.8%
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14.     Type Of Reporting Person (See Instructions)

        IN
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     This Amendment No. 1 amends and supplements the Schedule 13D, dated March
3, 2006 (the "Original Schedule 13D"), and filed by Steven G. Mihaylo ("Mr.
Mihaylo") with the Securities and Exchange Commission (the "SEC") on March 6,
2006, with respect to the common stock, no par value per share ("Common
Stock"), of Inter-Tel, Incorporated, an Arizona corporation ("Inter-Tel").
Capitalized terms used but not defined herein shall have the respective
meanings set forth in the Original Schedule 13D.

Item 4.       Purpose of Transaction.

     The response to Item 4 of the Original Schedule 13D is hereby amended and
supplemented by adding the following paragraphs at the end of such Item 4:

                  On April 3, 2006, Mr. Mihaylo sent a letter (the "April 3
         Letter") to the Board of Directors of Inter-Tel (the "Inter-Tel Board")
         proposing a meeting with the Inter-Tel Board to discuss a possible
         all-cash acquisition of Inter-Tel. Mr. Mihaylo stated in his letter
         that in connection with his review of alternatives, as described above
         in this Item 4, he has been discussing a possible arrangement between
         himself and Vector Capital (together with its affiliates, "Vector"), a
         technology-focused private equity fund with substantial experience
         investing in and acquiring technology companies, and that he and Vector
         have been meeting to discuss the possibility of together pursuing an
         acquisition of Inter-Tel and the manner in which that might best be
         effected. A copy of the April 3 Letter is filed as Exhibit 1 hereto and
         is incorporated herein by this reference.

                  On April 7, 2006, in accordance with the advance notice bylaw
         provisions that Inter-Tel adopted on March 29, 2006, Mr. Mihaylo
         delivered to Inter-Tel an advance notice of business and an advance
         notice of director nominations (such notices, the "Bylaw Advance
         Notices") to be brought before the Annual Meeting. In the Bylaw
         Advance Notices, Mr. Mihaylo informed Inter-Tel that he intended (1) to
         nominate a slate of three directors (including himself) for election at
         the Annual Meeting (the "Director Nominations") and (2) to introduce at
         the Annual Meeting several resolutions to be submitted to the vote of
         the shareholders (the "Shareholder Proposals"). The Shareholder
         Proposals include a resolution urging the Inter-Tel Board to arrange
         for the prompt sale of Inter-Tel to the highest bidder and resolutions
         to repeal recent amendments to Inter-Tel's bylaws that could have the
         effect of discouraging offers to acquire Inter-Tel . Mr. Mihaylo
         delivered to Inter-Tel the Bylaw Advance Notices in order to preserve
         his ability to communicate directly with Inter-Tel's shareholders and
         to solicit their support for his proposal to seek a prompt sale of
         Inter-Tel.

                  The Shareholder Proposals and the respective reasons therefor
                  are set forth below:

                  Proposal 1:       RESOLVED, that the shareholders of
                                    Inter-Tel, Incorporated ("Inter-Tel") urge
                                    the Inter-Tel Board of Directors to arrange
                                    for the prompt sale of Inter-Tel to the
                                    highest bidder.


                                    The reason for proposal 1 (the "Sell the
                                    Company Resolution" proposal) is to give all
                                    shareholders the opportunity to send a
                                    message to the Inter-Tel Board that the
                                    shareholders support the sale of Inter-Tel
                                    to the highest bidder.


                  Proposal 2:       RESOLVED, that the amendments to Section
                                    2.5 ("Special Meetings of Shareholders") of
                                    the Bylaws of Inter-Tel, Incorporated
                                    adopted by the Board of Directors on
                                    February 21, 2006 relating to the calling of
                                    a special meeting of shareholders for the
                                    purpose of considering any action to
                                    directly or indirectly facilitate a
                                    "business combination" are hereby repealed.


                  Proposal 3:       RESOLVED, that Section 2.12 ("Advance
                                    Notice of Shareholder Business") of the
                                    Bylaws of Inter-Tel, Incorporated adopted by
                                    the Board of Directors on March 29, 2006 is
                                    hereby repealed in its entirety.


                  Proposal 4:       RESOLVED, that Section 2.13 ("Advance
                                    Notice of Director Nominations") of the
                                    Bylaws of Inter-Tel, Incorporated adopted by
                                    the Board of Directors on March 29, 2006 is
                                    hereby repealed in its entirety.


                                    The reason for proposals 2, 3 and 4
                                    (collectively, the "Repeal the Bylaw
                                    Amendments Resolutions") is to give all
                                    shareholders the opportunity to repeal the
                                    amendments to Section 2.5 and to repeal in
                                    their entireties Sections 2.12 and 2.13 of
                                    the Inter-Tel Bylaws recently adopted by the
                                    Board of Directors. The recent amendments to
                                    Section 2.5 and the adoption of Sections
                                    2.12 and 2.13 of the Bylaws could have the
                                    effect of discouraging offers to acquire
                                    Inter-Tel. Together with the Sell the
                                    Company Resolution, the Repeal the Bylaw
                                    Amendments Resolutions would send a strong
                                    message to the Inter-Tel Board that the
                                    shareholders support the sale of Inter-Tel
                                    to the highest bidder and that the Board of
                                    Directors should not adopt amendments to the
                                    Bylaws that could discourage offers to
                                    acquire Inter-Tel.


                  Proposal 5:       RESOLVED, that the Bylaws of Inter-Tel,
                                    Incorporated are hereby amended to require
                                    the unanimous vote of all members of the
                                    Board of Directors in order to adopt any
                                    amendment to the Bylaws that could have an
                                    anti-takeover effect, including, without
                                    limitation, any advance notice requirements
                                    for the election of directors or the conduct
                                    of business at shareholder meetings or any
                                    change in the ability of shareholders to
                                    call a special meeting of shareholders.


                                   The reason for proposal 5 (the "Unanimous
                                   Vote Resolution") is to prevent the Inter-Tel
                                   Board from amending the Bylaws after the
                                   Annual Meeting to create new obstacles to the
                                   sale of Inter-Tel to the highest bidder or
                                   overturning the vote of the shareholders on
                                   the Repeal the Bylaw Amendments Resolutions
                                   without the unanimous vote of all members of
                                   the Inter-Tel Board. If any of the director
                                   nominees proposed by Mr. Mihaylo are elected
                                   at the Annual Meeting, then the Inter-Tel
                                   Board may not be able to obtain a unanimous
                                   vote on any such amendments, although the
                                   result of any such vote would depend upon the
                                   exercise of each such director's fiduciary
                                   duty at the time of the vote. Based upon the
                                   number of shares that Mr. Mihaylo
                                   beneficially owns and cumulative voting under
                                   Arizona law, Mr. Mihaylo will be able to
                                   elect at least one director at the Annual
                                   Meeting.


                  Proposal 6:       RESOLVED, that each and every provision
                                    of the Bylaws of Inter-Tel, Incorporated
                                    adopted by the Board of Directors after
                                    March 29, 2006, and prior to the adoption of
                                    this resolution is hereby repealed.


                                   The reason for proposal 6 (the "No Amendments
                                   Resolution") is to prevent the Inter-Tel
                                   Board from taking actions to amend the Bylaws
                                   to attempt to nullify or delay the actions to
                                   be taken by the shareholders at the Annual
                                   Meeting or to create new obstacles to the
                                   sale of Inter-Tel to the highest bidder.
                                   According to publicly available information,
                                   the most recent amendments to the Bylaws were
                                   adopted on March 29, 2006 and no amendments
                                   subsequent to that date have been publicly
                                   disclosed. If the Inter-Tel Board has adopted
                                   any amendments to the Bylaws since March 29,
                                   2006, or adopts any amendments to the Bylaws
                                   prior the Annual Meeting, the No Amendments
                                   Resolution would repeal all such amendments.

                  MacKenzie Partners, Inc. ("MacKenzie") has been retained to
         assist in the proxy solicitation, and Sitrick And Company Inc.
         ("Sitrick") has been retained to provide public relations services.

                  On April 10, 2006, Mr. Mihaylo sent a letter (the "April 10
         Letter") to the Inter-Tel Board to reaffirm his interest in meeting
         with the Inter-Tel Board or its advisors to discuss a possible all-cash
         acquisition of Inter-Tel led by Mr. Mihaylo, as expressed in the April
         3 Letter. A copy of the April 10 Letter is filed as Exhibit 2 hereto
         and is incorporated herein by this reference.

                  Also on April 10, 2006, Mr. Mihaylo issued a press release
         announcing that he had sent to the Inter-Tel Board the April 3 Letter
         and the April 10 Letter, and setting forth the text of the letters, and
         that he had delivered to Inter-Tel the Bylaw Advance Notices. A copy of
         the press release is filed as Exhibit 3 hereto and is incorporated
         herein by this reference.

                  Mr. Mihaylo plans to file with the SEC, and mail to
         Inter-Tel's shareholders, a proxy statement in connection with the
         Director Nominations and the Shareholder Proposals. The proxy statement
         will include information with respect to any other participants in the
         solicitation and a description of the direct and indirect interests of
         Mr. Mihaylo and any other participants in the solicitation. Investors
         are urged to read the proxy statement and any other relevant documents
         when they become available because they will contain important
         information. Investors will be able to obtain free copies of the proxy
         statement (when available) and other documents that Mr. Mihaylo files
         with the SEC through the web site maintained by the SEC at www.sec.gov.
         In addition, investors will be able to obtain a copy of the proxy
         statement (when available) from Mr. Mihaylo free of charge by
         contacting Mr. Mihaylo's proxy solicitor: MacKenzie Partners, Inc., 105
         Madison Avenue, New York, New York 10016, Tel: 212-929-5500, Fax:
         212-929-0308, email: proxy@mackenziepartners.com.

Item 5.       Interest in Securities of the Issuer.

     The response to Item 5(a) of the Original Schedule 13D is hereby amended
and supplemented by adding the following paragraph at the end of such Item
5(a):

                  Of these 5,179,498 shares of Common Stock, Mr. Mihaylo (i) is
          the holder of record of 144,000 shares and (ii) may be deemed to be
          the beneficial owner of the 5,035,498 shares of Common Stock held by
          The Steven G. Mihaylo Trust (the "Trust") because Mr. Mihaylo is the
          sole trustee of the Trust.

Item 6.       Contracts, Arrangements, Understandings or Relationships with
              Respect to Securities of the Issuer.

     The response to Item 6 of the Original Schedule 13D is hereby amended and
supplemented by adding the following paragraph at the end of such Item 6:

                  In connection with his review of alternatives, as described
         above in Item 4, Mr. Mihaylo has been discussing a possible arrangement
         between himself and Vector, and he and Vector have been meeting to
         discuss the possibility of together pursuing an acquisition of
         Inter-Tel and the manner in which that might best be effected.

Item 7.       Material to be Filed as Exhibits.

              Exhibit 1. Letter, dated April 3, 2006, from Steven G. Mihaylo to
              the Board of Directors of Inter-Tel.

              Exhibit 2. Letter, dated April 10, 2006, from Steven G. Mihaylo to
              the Board of Directors of Inter-Tel.

              Exhibit 3.   Press release, dated April 10, 2006, issued by
              Steven G. Mihaylo.








                                   SIGNATURE

     After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.


Dated:   April 10, 2006

                                                     /s/ Steven G. Mihaylo
                                                     ----------------------
                                                         Steven G. Mihaylo










                                 EXHIBIT INDEX

          Exhibit 1.   Letter, dated April 3, 2006, from Steven G. Mihaylo to
                       the Board of Directors of Inter-Tel.

          Exhibit 2.   Letter, dated April 10, 2006, from Steven G. Mihaylo to
                       the Board of Directors of Inter-Tel.

          Exhibit 3.   Press release, dated April 10, 2006, issued by
                       Steven G. Mihaylo.