Problem with Kerberos auth on AIX 5.3

[Dop]

I've been banging my head against this for a few days so I thought I'd see if anyone has an idea of what's going on.

AIX 5.3
OpenSSH 5.1p1
MIT Kerberos 1.6.3
zlib 1.2.3

Built with CC=cc and LDFLAGS=-brtl

When the client attempts to enter their kerberos password the daemon rejects it with the following message:
debug1: Kerberos password authentication failed: Not enough space.

If you try again the message changes to:
debug1: Kerberos password authentication failed: There is not enough memory available now.

I tracked that down to auth-krb5.c and a call to krb5_sname_to_principal().  If you comment out that call kerberos password authentication works just fine.  Unfortunately, that's not a good long term solution.  It smells like some crazy AIX memory allocation problem to me.  The ulimit settings appear fine and that's about the limit of my AIX knowledge.

Any thoughts?  

Thanks,
Mike