PDO sqlsrv for MSSQL on CodeIgniter 2.1.1

[eluser]jonldavis[/eluser]
I've been using the sqlsrv driver for a month or so with CI v2.1.0 successfully, but I've been wanting to take advantage of some of the PDO features you can't get with the plain driver (my DBA wants to use output parameters from stored procedures, and it seems that isn't supported by the MS driver directly).

However, when I pulled the v2.1.2 code and copied it to my server, my database connection was totally hosed, wouldn't even connect with sqlsrv or PDO.

Checking in database/drivers/sqlsrv, it seems to have reverted back to the previous connection problem (http://ellislab.com/forums/viewthread/197527/).

Don't know enough about PDO to look into it, though I tried ngatcharius's fix without success.

For now, stepping back to CI v2.1.0 until I have time to figure out what's wrong.