In case it's of interest, I just came across some exclamation
points in a printed Sinhalese edition of the mahasatipatthana sutta.
The exclamation points mark inserted vocatives, such as:
katha^n ca
bhikkhave! bhikkhu kaaye kaayaanupassii viharati?
This was no doubt
added at a late stage to help the reader. The printers or typesetters
of this edition occasionally messed up and used question marks for this
function.
I'm out of town and only have sporadic e-mail contact.