[CentOS] su, context(selinux?) 2nd prompt

With a recent update of CentOS4, su's behavior has changed, in that after
prompting for password, also prompts for (selinux?) context.  I'm seeing
something like:
$ su
Password:
Your default context is root:system_r:unconfined_t.

Do you want to choose a different one? [n]


kde's kdesu barfs on this second prompt.  Any way to disable this second
prompt?

-- Rex