Congrats to Jiri Cincura and the developers who have just released the Firebird provider which includes EF support!
You can read about the release (and a happy company which is using it) on Jiri's blog at http://blog.vyvojar.cz/jirka/archive/2009/05/22/ann-firebirdclient-2-5-final-released.aspx.
You can download the release from http://www.firebirdsql.org/index.php?op=files&id=netprovider
