-bash: [: : integer expression expected

Anybody seen this before?

user@host:~$ ssh user@xxxxxxxxxx
Last login: Thu Sep 14 10:36:02 2006 from xxx.xxx.xxx.xxx
-bash: [: : integer expression expected
user@server:~$

This starts to happen if I move to libnss-ldap 251 (previously running
238), which seems slightly odd to me as I don't see how this will be
interfering with the users shell.

Also, this not limited to bash, as if I change the users shell
to /bin/sh I get '-sh: [: : integer expression expected'

Nothing abnormal in syslog, messages, authlog.

Ummm, any deas?

Regards

- Daniel