ActiveState Komodo Edit?

[Trent Mick]

>> If you make line numbers visible (View -> View Line Numbers) then
>> you can do what you want in the line numbers gutter.
> 
> I am using the free editor-only Komodo Edit. Apparently that does not
> work here. 

I believe it was a recent change. What version are you using? You could 
try the latest nightly build:
   http://downloads.activestate.com/Komodo/nightly/

Cheers,
Trent

-- 
Trent Mick
trentm at activestate.com