Reporting a bug in Mac GUI

Hi list,

when typing a function name and then an empty set of parentheses, such 
as ls(), if the () are typed very quickly the command window spews a 
couple lines of red stuff with several NSthis and NSthat, then makes a 
line that looks like ls()(    -- with the extra parens  --  and 
processes no further typed input. The app must be quit and restarted in 
order to get unlocked from this stuck mode.