when inserting a record into sql server (via odbc) doctrine fails to get last inserted ID

in Doctrine/Sequence/Mssql.php the function lastInsertId() fails to retrieve the last inserted ID when inserting a record. Because the major release of my sql server is bigger than 8, it chooses $query = 'select SCOPY_IDENTITY()' which does not return a number (in fact it does not return anything), although the record IS inserted succesfully. The backtrace is attached.
If, on the other hand, I force doctrine to use 'select @@IDENTITY' the query does return the correct number and everything goes fine!
So I think the conditions which query to choose is incorrect. I tried both queries in SQL server itself and both queries returned the right number. But one of them gets lost somewhere when using it in doctrine.