I've have a board that used to run everything off a 48MHz clock. We have a new board revision that attempts to switch this with a 62.5MHz clock (48MHz is still available for USB clock) and we aren't able to program it anymore.
I'm attempting to program it using PE Micro's "PROGCFZ Programmer" and a ColdFire BDM connector and we get the error "35 - Not able to access processor. Try a software reset." If we jumper back to the 48MHz clock everything programs fine.
The 5272 can run up to 66MHz so I would assume 62.5MHz is a valid operating frequency.