Connection Problem to Oracle V7.15 when using XA

I am using Oracle V7.15 on an RS/6000 running AIX3.2.5. I have an OCI application that uses the Oracle XA interface with an Encina transaction manager My XA open string is defined as follows:

                   "Oracle_XA+Acc=P/userid/passwd+SesTm=0+LogDir=/home/encina/log/Oracle"

I am sometimes successful at making a connection and executing application queries. However, during the course of a transaction, I get a spurious break in the connection resulting in a global rollback. My xa_*.trc file produces the following diagnostics:

>> 142547.50625.0:
>> ORACLE XA: Version 1.0.3.0.0 - Production. RM name = 'Oracle_XA'.
>>
>> 142547.50625.0:
>> xaoend: XA_RBROLLBACK; upisdt rtn ORA-3114.
>>
>> 142548.50625.0:
>> ORA-03114: not connected to ORACLE
>>
>>
>> 142548.50625.0:
>> xaoend: upisdl rtn ORA-3114.
>>
>> 142548.50625.0:
>> xaoswitch: XAER_RMERR; upixaxs rtn ORA-3114.
>>
>> 142548.50625.0:
>> ORA-03114: not connected to ORACLE
>>
>>
>> 142548.50625.0:
>> xaorollback: xaoswitch rtn -3.

Why am I losing connections to the listener? I did not configure this instance of Oracle myself and have no clue about what to do? Can anyone out there help me? I suspect that it is a configuration problem.

Regards,
Dex

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Dexter P. Bradshaw                   \ Internet: dpbradsh_at_bluebox.uwaterloo.ca
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