|Exhibit 4.7








SUPPLEMENTAL INDENTURE



SUPPLEMENTAL
 INDENTURE (this Supplemental Indenture) executed as of February 26, 2004, by and among Arch Wireless
 Holdings, Inc., a Delaware corporation (the Company), Arch Wireless Communications, Inc., a Delaware
 corporation (Arch), Arch Wireless, Inc., a Delaware corporation (the Parent), and the direct and
 indirect subsidiaries of the Parent listed on Schedule I hereto (such subsidiaries, the Subsidiary
 Guarantors, and together with Arch and the Parent, herein the Guarantors) and The Bank of New York,
 a New York banking corporation, as Trustee (the Trustee).



RECITALS



WHEREAS,
 the Company, the Guarantors and the Trustee have heretofore executed and delivered that certain Indenture,
 dated as of May 29, 2002, as amended by the Supplemental Indentures dated as of August 14, 2002, March
 6, 2003, June 12, 2003 and September 26, 2003 (the Indenture), with respect to the Companys 12% Subordinated
 Secured Compounding Notes Due 2009 (the Notes);



WHEREAS,
 Section 8.02 of the Indenture provides that the Company and the Guarantors, when authorized by a Board
 Resolution, and the Trustee, together with the written consent of the Majority Noteholders, may, under
 certain circumstances, enter into an indenture or indentures supplemental to the Indenture for the purpose
 of adding any provisions to or changing in any manner or eliminating or waiving (subject to Section
 4.03 of the Indenture) any of the provisions of the Indenture or of modifying in any manner the rights
 of the Holders under the Indenture;



WHEREAS,
 the Company desires to amend certain sections of the Indenture to waive compliance with certain covenants
 for certain periods, and in connection therewith, the Company has been soliciting written consents of
 the Holders to the amendments to the Indenture set forth herein (and to the execution of this Supplemental
 Indenture), and the Company has now obtained such written consents from the Holders of a majority in
 the aggregate principal amount of the outstanding Notes; accordingly, this Supplemental Indenture is
 authorized pursuant to Section 8.02 of the Indenture; and



WHEREAS,
 the execution and delivery of this Supplemental Indenture has been duly authorized by the parties hereto,
 and all other acts necessary to make this Supplemental Indenture a valid and binding supplement to the
 Indenture, effectively amending and supplementing the Indenture as set forth herein, have been duly
 taken;



NOW,
 THEREFORE, in consideration of the above premises and for other good and valuable consideration, the
 receipt of which is hereby acknowledged, it is mutually agreed, for the equal and proportionate benefit
 of all Holders, as follows:




ARTICLE ONE



Upon
 execution of this Supplemental Indenture by the Company and the parties hereto, then automatically (without
 further act by any person) with respect to all outstanding Notes, the Indenture is hereby amended in
 the following respects:
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | 1.1 | Section 10.21 of the Indenture shall be deleted in its entirety, and the following is substituted in lieu thereof:
| | --- | ------------------------------------------------------------------------------------------------------------------

|SECTION 10.21 Minimum EBITDA.



From
 and after the Trigger Date, the Note Parties shall have, as of the last day of each quarter set forth
 below, EBITDA for such quarter of not less than the following:
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|Quarter Ending     | Minimum Quarterly EBITDA(dollars in millions)
|------------------ | ---------------------------------------------
|June 30, 2002      | 46.5                                         
|September 30, 2002 | 45.5                                         
|December 31, 2002  | 42.9                                         
|March 31, 2003     | 41.0                                         
|June 30, 2003      | 36.5                                         
|September 30, 2003 | 34.3                                         
|December 31, 2003  | 30.9                                         
|March 31, 2004     | 26.9                                         
|June 30, 2004      | Waived/Compliance not req'd                  
|September 30, 2004 | Waived/Compliance not req'd                  
|December 31, 2004  | Waived/Compliance not req'd                  
|March 31, 2005     | Waived/Compliance not req'd                  
|June 30, 2005      | 33.9                                         
|September 30, 2005 | 34.2                                         
|December 31, 2005  | 34.7                                         
|March 31, 2006     | 33.1                                         
|June 30, 2006      | 34.6                                         
|September 30, 2006 | 36.1                                         
|December 31, 2006  | 37.4                                         
|March 31, 2007     | 36.6                                         
|June 30, 2007      | 36.1                                         
|September 30, 2007 | 35.4                                         
|December 31, 2007  | 34.6                                         
|March 31, 2008     | 33.8                                         
|June 30, 2008      | 33.3                                         
|September 30, 2008 | 32.5                                         
|December 31, 2008  | 31.8                                         
|March 31, 2009     | 31.1                                         

| | 1.2 | Section 10.22 of the Indenture shall be deleted in its entirety, and the following is substituted in lieu thereof:
| | --- | ------------------------------------------------------------------------------------------------------------------

|SECTION 10.22 Minimum Direct Units in Service.



From
 and after the Trigger Date, the Note Parties will maintain a number of Direct Units in Service as of
 the last day of the quarter, not less than as set forth opposite such day:
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|Quarter Ending     | Minimum Direct Units in Service(units in thousands)
|------------------ | ---------------------------------------------------
|June 30, 2002      | 4,215.2                                            
|September 30, 2002 | 4,002.7                                            
|December 31, 2002  | 3,819.3                                            
|March 31, 2003     | 3,630.1                                            
|June 30, 2003      | 3,558.1                                            
|September 30, 2003 | 3,301.6                                            
|December 31, 2003  | 3,055.4                                            
|March 31, 2004     | 2,909.4                                            
|June 30, 2004      | Waived/Compliance not req'd                        
|September 30, 2004 | Waived/Compliance not req'd                        
|December 31, 2004  | Waived/Compliance not req'd                        
|March 31, 2005     | Waived/Compliance not req'd                        
|June 30, 2005      | 2,837.6                                            
|September 30, 2005 | 2,779.5                                            
|December 31, 2005  | 2,722.6                                            
|March 31, 2006     | 2,600.3                                            
|June 30, 2006      | 2,566.4                                            
|September 30, 2006 | 2,532.8                                            
|December 31, 2006  | 2,499.7                                            

| | 1.3 | Section 10.23 of the Indenture shall be deleted in its entirety, and the following is substituted in lieu thereof:
| | --- | ------------------------------------------------------------------------------------------------------------------

|SECTION 10.23 Minimum Consolidated SRM Revenues.



From
 and after the Trigger Date, the Note Parties shall maintain, as of the last day of each quarter set
 forth below, consolidated SRM revenue for such quarter of not less than the Minimum Quarterly Consolidated
 SRM Revenue listed below:
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

|Quarter Ending     | Minimum QuarterlyConsolidated SRM Revenue(dollars in millions) | Planned One Way SRMRevenue(dollars in millions) | Planned Two Way SRMRevenue (dollars inmillions)
|------------------ | -------------------------------------------------------------- | ----------------------------------------------- | -----------------------------------------------
|June 30, 2002      | 174.8                                                          | 174.9                                           | 30.8                                           
|September 30, 2002 | 166.6                                                          | 162.2                                           | 34.0                                           
|December 31, 2002  | 160.7                                                          | 151.7                                           | 37.3                                           
|March 31, 2003     | 153.7                                                          | 142.5                                           | 43.8                                           
|June 30, 2003      | 133.1                                                          | 133.8                                           | 48.2                                           
|September 30, 2003 | 124.2                                                          | 125.6                                           | 48.5                                           
|December 31, 2003  | 116.2                                                          | 117.9                                           | 53.3                                           
|March 31, 2004     | 107.5                                                          | 109.1                                           | 55.5                                           
|June 30, 2004      | Waived/Compliancenot req'd                                     | 100.9                                           | 62.6                                           
|September 30, 2004 | Waived/Compliancenot req'd                                     | 93.4                                            | 66.5                                           
|December 31, 2004  | Waived/Compliancenot req'd                                     | 86.4                                            | 70.3                                           
|March 31, 2005     | Waived/Compliancenot req'd                                     | 81.5                                            | 70.7                                           
|June 30, 2005      | 120.3                                                          | 76.9                                            | 73.5                                           
|September 30, 2005 | 119.8                                                          | 72.6                                            | 77.2                                           
|December 31, 2005  | 117.4                                                          | 68.5                                            | 78.3                                           
|March 31, 2006     | 112.6                                                          | 64.4                                            | 80.8                                           
|June 30, 2006      | 112.1                                                          | 60.6                                            | 84.1                                           
|September 30, 2006 | 111.2                                                          | 57.0                                            | 86.5                                           
|December 31, 2006  | 110.8                                                          | 53.7                                            | 89.3                                           
|March 31, 2007     | N/A                                                            | 50.5                                            | 91.4                                           
|June 30, 2007      | N/A                                                            | 47.5                                            | 92.8                                           
|September 30, 2007 | N/A                                                            | 44.6                                            | 93.8                                           
|December 31, 2007  | N/A                                                            | 41.9                                            | 94.3                                           
|March 31, 2008     | N/A                                                            | 39.4                                            | 94.8                                           
|June 30, 2008      | N/A                                                            | 37.0                                            | 95.5                                           
|September 30, 2008 | N/A                                                            | 34.8                                            | 95.7                                           
|December 31, 2008  | N/A                                                            | 32.8                                            | 96.0                                           
|March 31, 2009     | N/A                                                            | 30.7                                            | 96.3                                           

|ARTICLE TWO



2.1
 All terms used in this Supplemental Indenture which are defined in the Indenture and not otherwise defined
 herein shall have the meanings assigned to such terms in the Indenture.



2.2
 All of the provisions of this Supplemental Indenture shall be deemed to be incorporated in, and made
 part of, the Indenture, and the Indenture, as amended and supplemented by this Supplemental Indenture,
 shall be read, taken and construed as one and the same instrument and shall be binding upon all the
 Holders.



2.3
 This Supplemental Indenture may be executed in any number of counterparts, each of which so executed
 shall be deemed to be an original, but all such counterparts shall together constitute but one and the
 same instrument.



2.4
 In case any provision in this Supplemental Indenture shall be invalid, illegal or unenforceable, the
 validity, legality and enforceability of the remaining provisions shall not in any way be affected or
 impaired thereby.



2.5
 Nothing in this Supplemental Indenture, express or implied, shall give any person, other that the parties
 hereto and their successors hereunder and the Holders, any benefit or any legal or equitable right,
 remedy or claim under this Supplemental Indenture. Except as expressly supplemented or amended as set
 forth in this Supplemental Indenture, the Indenture is hereby ratified and confirmed, and all the terms,
 provisions and conditions thereof shall be and continue in full force and effect. The Trustee accepts
 the trusts created by the Indenture, as amended and supplemented by this Supplemental Indenture, and
 agrees to perform the same upon the terms and conditions in the Indenture as amended and supplemented
 by this Supplemental Indenture.



2.6
 The Trustee shall not be responsible in any matter whatsoever for or in respect of the validity or sufficiency
 of this Supplemental Indenture, except with respect to the execution hereof by the Trustee, or for or
 in respect of the recitals contained herein, all of which are made solely by the Company and the Guarantors.


_________________


IN
 WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly executed, all
 as of the day and year first written above.
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| | Arch Wireless, Inc.Arch Wireless Holdings, Inc.Arch Wireless Communications, Inc. MobileMedia Communications, Inc.Arch Wireless Operating Company, Inc. Arch Wireless License Co., LLCPaging Network Canadian Holdings, Inc.
| | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

| |  | As to each of the foregoing:BY:NAMETITLE
| |  | ----------------------------------------------------------------------------------

| |  | The Bank of New York, as Indenture Trustee Collateral AgentBY:NAMETITLE
| |  | -----------------------------------------------------------------------------------------------------------------

|Schedule I



Arch Wireless, Inc.Arch Wireless Communications,
 Inc. MobileMedia Communications, Inc. Arch Wireless Operating Company, Inc. Arch Wireless
 License Co., LLC Paging Network Canadian Holdings, Inc.
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------