SPX listener on NT 3.51 goes down constantly!

Hi there,

I have been using Oracle 7.2.3 on NT 3.51 for three month. It works well. Users are connecting the server using SQL*NET 2.2 for TCP/IP from their PC. Now we try to connect some users to the server through SPX/IPX. The listener worked once a while then stopped listening for SPX. It is the same listener that listens TCP connections. It never stops listening TCP/IP connections. I wonder where is the problem. Here is the listener.ora file on NT server and tnsnames.ora file. Could any one give me any hints?

-- 
Bo Lu
Senior Programmer/Analyst
Hospital and Clinical Informatics, U. of Utah
801-581-5964, bo.lu_at_hsc.utah.edu

################
# Filename......: listener.ora
# Node..........: local.world
# Date..........: 24-MAY-94 13:23:20
################
LISTENER =
  (ADDRESS_LIST =
        (ADDRESS=


          (PROTOCOL= IPC)


          (KEY= oracle.world)


        )
        (ADDRESS=


          (PROTOCOL= IPC)


          (KEY= ORCL)


        )
        (ADDRESS=


          (COMMUNITY= NMP.world)

          (PROTOCOL= NMP)

          (SERVER= ACIS1)


          (PIPE= ORAPIPE)


        )
        (ADDRESS= 


          (COMMUNITY= TCP.acis)

          (PROTOCOL= TCP)

          (Host= acis1)


          (Port= 1521)


        )
        (ADDRESS= 


          (COMMUNITY= TCP.acis)

          (PROTOCOL= TCP)

          (Host= acis1)


          (Port= 1526)


        )
        (ADDRESS= 


          (COMMUNITY= SPX.acis)

          (PROTOCOL= SPX)


          (Service= acis1_lsnr)


        )
  )
STARTUP_WAIT_TIME_LISTENER = 0
CONNECT_TIMEOUT_LISTENER = 10
TRACE_LEVEL_LISTENER = ADMIN
SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = ORCL)
    )
  )
PASSWORDS_LISTENER = (oracle)


################
# Filename......: tnsnames.ora
# Name..........: med.utah.edu
# Date..........: 05-NOV-95 13:05:34
# Update........: B. Lu March 3, 1996
################

# SPX/IPX
ACIS1X.MED.UTAH.EDU = 
  (DESCRIPTION = 
    (ADDRESS_LIST = 
        (ADDRESS = 


          (COMMUNITY = spx.acis)

          (PROTOCOL = SPX)


          (Service = acis1_lsnr)


        )
    )
    (CONNECT_DATA = (SID = ORCL)
    )
  )