Actually GPS's are NOT the same. mKGPS 1 uses uBlox LEA 4H and MKGPS 2.1 uses the newest uBlox LEA 6S.
Here is the difference between the two:
http://www.mikrokopter.de/ucwiki/en/MKGPS
Nick
Actually the latest is 0.88n released on 06.JUL.2012
http://svn.mikrokopter.de/listing.php?repname=FlightCtrl&path=%2Ftags%2FV0.88n%2FHex-Files%2F&#A3bb06a3aaa488973597ac0c493efb84d
Nick