Disk quotas with Webmin & OSXS 10.3.5

I have successfully integrated my OSX Servers with Active Directory 2003 without modifying the schema and everything appears to be working OK for the most part. I have discovered one problem though. Since we did not modify the AD schema I cannot use WGM to set disk quotas for any of my users. Well I decided to use Webmin to put a GUI face to the CLI quota commands. I have set quotas for all my users but they don't appear to be enforced! I have set everyone's soft limit to 110000 blocks and the hard limit to 200000 blocks (approx 110MB and 200MB respectively) but I have users who have managed to put 600MB or more in their home folders!!! Has anyone had any luck getting Webmin to work with disk quotas on OSX Server?