Red Hat Appears to Ignore Secondary Groups for LDAP Users

[Tim P. Starrin]

On Red Hat Enterprise Linux (RHEL) 4 Update 6 with the latest patches

Given the LDAP user "t-bone" with the following group set...

    % id
    uid=9066(t-bone) gid=121(a00121) groups=121(a00121),144(a00144) \
        context=user_u:system_r:unconfined_t

    % groups
    a00121 a00144


The following operations that should work on a Linux ext3 file system,
fail...

    % ls -la
    drwxr-x---  2 root   a00144 4096 Mar 19 13:29 a00144
    -r--r-----  1 root   a00144   29 Feb 27 18:34 date

    % ls a00144
    ls: a00144: Permission denied

    % cat date
    cat: date: Permission denied


Note that file and directory access via the primary group, gid=121(a00121),
works fine.

Did I setup something wrong or is this a real bug?

Thanks.