I was in the process of change all the $CFG->dbtype ocurrences to the new $CFG->dbfamily (MDL-7061) when I've seen that both in the upgrade code and in lib.php there are situations where the module won't work if we are using MSSQL or Oracle.

Perhpas the upgrade code isn't critical (because it's old), but some "IF" and "CASE" clauses should be fixed to work under such DBs.