Investigating a little further, it seems that Emacs is not the only X client affected. So far though, meld is the only other app I've found that is affected in a similar (although more severe) manner. Haven't yet had a chance to try other combinations of OS on each end with meld (affected = Ubuntu X server, meld on Debian over ssh).
Cheers, Nick -- Nick Phillips / nick.phill...@otago.ac.nz / 03 479 4195 # These statements are mine, not those of the University of Otago