Informix backup failed

[nickl]

When I use NMI2.0 to backup Informix (IDS)7.31UC2 on AIX sp2(AIX4.3.2),I meet error.
When I finished backup dbspace(80GB),but logical log can not be switched and backup,so group will hang until inactivity,and bar_act log said
"2001-09-18 17:06:58 284274 35594 WARNING: BAR_XFER_BUF_SIZE exceeded maximum allowed limit. Changing buffer size to 61440.
2001-09-18 17:06:58 284274 35594 /home/informix/bin/onbar_d -b -L 0 rootdbs
2001-09-18 17:06:59 284274 35594 Begin level 0 backup rootdbs.
2001-09-18 17:06:59 284274 35594 Successfully connected to Storage Manager.
2001-09-18 17:07:39 284274 35594 Completed level 0 backup rootdbs.
2001-09-18 17:07:43 284274 35594 Begin backup logical log 313.
2001-09-18 17:07:43 284274 35594 Successfully connected to Storage Manager.
2001-09-18 17:07:43 284274 35594 XBSA Error (BSACreateObject): A system error occurred. Aborting XBSA session.
2001-09-18 17:07:58 284274 35594 Process 284274 received signal 2. Process will exit after cleanup."


I backup another Informix (database is 180GB)with the same platform and same version,it tell me :"blocked:archive",but no error message.
Can you tell me how to solve this problem,