Thanks for the comments.  I checked the system logs and we are not using
an Adaptec SCSI controller.  It is a Fusion MPT (integral part of the Intel
mother board), so I guess that rules out the aic79xx driver as the problem.
 Doesn't it?

     The other comment was that our kernel, 2.4.21-37.EL.XFSsmp, is too old
for SCSI tape drives and I need at least 2.4.24.  I do not see any SCSI errors
in any of the logs.  Should I see errors in any log?  I only have problems
when the number of files gets over some unknown limit.  We've got 3 systems
here, all running the same version of SL and have the same tape drive (the 3rd
one has an Adaptec controller).  I haven't seen any problems on the 3rd
system, but I haven't tried pushing the number of files on the system to test
it.  The problem with trying to upgrade to a newer kernel is that SL doesn't
have an XFS capable kernel newer than what I have installed, at least not for
the SL 3.0.x series.  Any ideas?

     Thanks for the help.