I would like to use MSSQL too but I have some problems... for example, using the latest version available by CVS, I have this error:

Database query failed. Error received from database was #0: for the query: UPDATE mantis_user_table
SET login_count=login_count+1
WHERE id='1'

It's very strange that the error is #0... I have tried that query on MSSQL using Query Analyzer and it's ok...
What is your experience using Mantis & MSSQL?
Thank you for your help.