Netware 5 and ArcServeIT 6.6

I have a Netware 5 server w/ SP5 and ArcServeIT 6.6. Every night this week and a few various nights over the past 2 months ArcServe is abending the server. ArcServe is no help what so ever (no big suprise!!) The only thing that shows up in the error log is the typical abend error (Server experienced a critical error and has terminated the process). I have unistalled ArcServe and reinstalled it, tried running manuel jobs, and have had no luck in getting the backups running….
Thoughts / Suggestions????