Remote Assistance stops working

Since early March when the DST patch was installed, we have an intermittent problem where someone trying to offer Remote Assistance gets permission denied immediately. Looking at the local groups we can see that the correct users are there. The group policy is flowing as expected. This problem is on PCs only, all all laptops seem to work as expected. Only Admins can RA from these PCs. Around this same timeframe Windows 2003 sp1 was installed on our Domain controllers. Anyone else have this problem?