setuid programs under "sarge" and "woody"

[Douglas Bates <bates@stat.wisc.edu>]

I run Debian 3.1 (testing) on several i386 systems and Debian 3.0 on
one i386 system.  Our systems group recently switched their backup
system that had been using /sbin/dumpe2fs to a version of tar.  

We have their tar program installed under the wsbackup login.  The
program is owned by root.root and has setuid and setgid permissions.


505$ ls -la
total 12
drwxr-sr-x    2 wsbackup wsbackup     4096 Oct 30 11:02 .
drwxr-sr-x    4 wsbackup wsbackup     4096 Oct 30 10:58 ..
-rwsrwsr-x    1 root     root         1889 Oct 30 11:02 sushiRunLinuxTar

Apparently the remote dumping system gets error messages of the form 

> >From the backup logs:
> 
> bombus-lucorum(3290):20021031.022744:2002.10.31:LinuxRmtTar:
> /u5: Stderr: Can't do setuid
> 
> ...and so on
> 
> It seems the script is being found, but has errors/doesn't
> execute/something.

Is there something else I should do to allow this program to run
setuid root?