samba - Oct 2003 - initialise_groups/initgroups input/output error

Hello everyone,

I did a little searching and didn't come up with much on this.
I just upgraded our Samba server from 2.2.3a to 2.2.8a to get it running on
the latest 2.2.x release.
After doing this, "Unable to initgroups, Error was Input/output error"
messages are showing up in all the smbd log files (except log.smbd)
regularly. We've never had this problem before with 2.2.3a.

Example:
[2003/10/30 07:54:16, 0] smbd/sec_ctx.c:initialise_groups(244)
  Unable to initgroups. Error was Input/output error
[2003/10/30 08:06:05, 0] smbd/sec_ctx.c:initialise_groups(244)
  Unable to initgroups. Error was Input/output error
[2003/10/30 08:20:19, 0] smbd/sec_ctx.c:initialise_groups(244)
  Unable to initgroups. Error was Input/output error

Any ideas?

Thanks,
Jason