Dev32.ser Msg fault


we have a problem with Dev32.ser (version 4.23I) on a 386 PC-104 board.
After 1-3 hours it stops sending data on /dev/ser1,
traceinfo shows following message:

Jun 15 17:44:53 2 00001012 Msg fault 23 0004 0001 //1/bin/Dev32

After slay and restart of Dev32.ser it works again.
Any hints would be fine.

mbs GmbH