This isn't a particularly high-priority bug, but it seems fairly straightforward to fix. It presumably appears if you recover >= 1000 HP in combat, which isn't a crazy edge case.
KoL combat said:
Your wounds fly away on a refreshing spring breeze. You gain 4,574,802 hit points.
Revision 16000 changes the patterns to be a digit followed by any number of digits or commas. That will protect it from matching against a single comma - which probably will never happen in the strings it is used on, but, just in case...
