the time in pokemon crystal is not in sync. it's too slow. you set the time correctly but as you play, the time falls behind.
The reason is that the time is synced with the Gameboy CPU time instead of the real time as retrieved from the device. It is better to use the real time?
i think phone time would be better (i started this bug report)
this also fixed the crazy time thing i mentioned in the forums (which weren't working last time i checked).
fixed in SVN rev. 297