Apparently the fix for this is to use the "novj" option for pppd. This
is done in kde using the "setop"
menu in the Kppp dialer, then "pppd arguments".
Seems to fix the problem on my machine, but can't be entirely sure, due
the the unpredictable-intermittent
nature of the problem. See man page for pppd for what you're actually
doing here.
--
Peter Reiner