It does not work with SQL out of the box. You could get it to work with SQL but i expect that would be a pretty big undertaking. The least of which would include re-writing and replacing the support/include/mysql.php with one that calls on the sql database. (ie change all the mysql_ function calls for mssql_ function calls.) You would also have to re-write the support/install/install.php to get it to install.
