The performance of this can not be that great.  I wouldn't recommend 
hitting the calls table during authentication for anything.  What you
might do is use a seperate table (check out the timeusages and
timelimits
tables) to keep a running tally for each user over the current time
period.  Then you can modify the calls trigger to update the table for
that user, etc.
--Dale E. Reed Jr. Emerald and RadiusNT__________________________________________IEA Software, Inc. www.iea-software.com
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