Problems with TDEsu

For quite a while now I've been unable to use TDEsu to open utilities that require root access, e.g. TDM configuration. TDEsu freezes after I enter the root password and press Enter. When I run it from the command line I see Looking at /opt/trinity/bin/tdesud, I saw that indeed, it was not sgid, so I set that bit; but it still hangs, albeit without the message. I see that there are four programs associated with this function: Should other bits be set for one or more of these? Is there a missing entry in /etc/group? What else should I look for? N.B. I have tried reinstalling the package containing TDEsu, but that hasn't helped. Leslie