[OpenAFS] vmalloc troubles with 1.4.2

[Mike Dopheide]

System:
RHEL3 Kernel 2.4.21-47.ELsmp
OpenAFS 1.4.2 (rebuilt locally from fc4 SRPM)

I've got a system that averages about 40-50 users.  We recently upgraded 
the box to OpenAFS 1.4.2 and it was stable for about a month.  However, 
over the last week and a half it's crashed three times with:

Dec  4 13:18:03 osage kernel: afs_osi_Alloc: Can't vmalloc 4524 bytes.
Dec  4 13:18:03 osage kernel: crget: No more memory for creds!
Dec  4 13:18:05 osage kernel: Unable to handle kernel NULL pointer
dereference at virtual address 00000000

In my search of old threads it sounds like it could be related to PAG 
garbage collection.  That appears to already be turned on:

[root@osage dopheide]# cat /proc/sys/afs/GCPAGs
1

Any other things I can check out?

-Mike