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                           IBM ECA
              Engineering Change Announcement

Parts removed from this machine and returned to IBM must be genuine,
                      unaltered IBM Parts

         IBM World Trade Corporation, CE Department Germany
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 EC NUMBER         :  ECD17637     DATE             : 92-10-29
 MANDATORY         :  N
 AUTOMATIC SHIPMENT:  N            SERVICE CODE     : 33
 PARTS SOURCE      :  YASU         AVAILABILITY DATE: 92/10
                                                                                
 PURPOSE:                                                                       
 This ECA provides replacement EPROMs for affected Token Ring                   
 Network 16/4 Adapter/A , to prevent the following symptoms when                
 using application of"NetWare3.1""LAN Server2.0"or"Communication                
 Manager(ES J1.0)(OS/2 Ver2.0 Extended Service)"                                
                                                                                
   -Loss of communication between the Server and Requester.                     
   -Lost sessions                                                               
   -Server hang or lock-up                                                      

 Type             Machines Affected                             
 Mod.  With       and/or Feature/Device    B/M to be  Serv Syst 
 Stg.  B/M        Description              Installed  Hour Hour 

 Plant 98                                                       

 PS/55 B/MBASIC   TOKEN RING NETWORK       B/M48G9619 00.7 00.5 
  ALL             16/4 ADAPTER/A                                
                  SEE PHYSICAL CHECK AND                        
                  NOTE.                                         

                                                                                
 PHYSICAL CHECK:                                                                
 Affected Token Ring 16/4 Adapter/A can be identified by the
 card P/N:74F3306 or 74F8406.  (Note:Card P/N is not FRU P/N)
                                                                                
 You can also check the microcode level by running the token
 ring diagnostics from the reference diskette.
 If level A58769B or A78064 is present, The affected EPROMs are                 
 on the adapter.                                                                
                                                                                
 PREREQUISITES: NONE                                                            
                                                                                
 COMPANION: NONE                                                                
                                                                                
 CONCURRENT: NONE                                                               
                                                                                
 DETAIL:                                                                        
 Replace two EPROMs at location ZM18 and ZM19 on the Token Ring                 
 16/4 Adapter/A.                                                                
                                                                                
      Affected EPROM P/N               New EPROM P/N                            
      ------------------               ---------------                          
      74F9325/74F9326 or    ------->   92F4538/92F4539                          
      25F9523/25F9524                                                           
                                                                                
 NOTES:                                                                         
 The following table says affected machines.                                    
                                                                                
    SoftWare         S/R        OS/2 Version        FBM**                       
    ---------------  ---------  ------------------  ---                         
    ES J1.0          Server     1.3/2.0(all)          X                         
    ES J1.0          Requester  1.3/2.0(all)          X                         
    LAN Server J2.0  Server     1.3/2.0(all)          X                         
    LAN Server J2.0  Requester  1.3/2.0(all)          X                         
    Netware          Server     1.3/2.0(all)          X                         
    Netware          Requester  1.3/2.0(all)         OK                         
    OS/2 EE          Server     1.2/1.3(except 2.0)  OK                         
    OS/2 EE          Requester  1.2/1.3(except 2.0)  OK                         
                                                                                
            **Note:X means FBM required                                         
                   OK means "Not need FBM"                                      
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