Hello everybody
Ran into the same problem syncing GPS with the time-library. Solution was easy but hard to find:
Sync (routine defined with setSyncProvider) is executed with every call of now() after syncInterval has expired. Just place now() somewhere in the loop() portion of your program.
See also: http://www.adafruit.com/forums/viewtopic.php?f=31&t=36378
Greetings
hpb