BTW if the fix above doesn't work the guys over at SDX have a number of other things you can try. The ##GPSCLRX# worked for me for about a day then stopped. I wound up having to use the modified config file option. Tried a few of the others with no luck. From what I gather it's pretty hit-and-miss as to which one will actually fix your phone.
GPS Troubleshooting Guide - Hardware and Software
Probably the best collection of fixes for GPS I have found on the web right there in that one post. Enjoy!