Depends...
If I remember correctly, the original Celeron processors had no FSB lock.
Then Intel realized the Celeron was way too good of a product and was outcompeting the more expensive Pentium II - thus they then locked the FSB to 66MHz.
And I'm not sure at what point, but the new Celerons are back locked at 100MHz FSB.
So it really depends on which particular Celeron processor you've got. Which speed have you got?