Read-only or read-write proofreading???

For RO you may want to try Syntax::Highlight::Mason

For RW I suggest emacs* :-)

If Komodo doesn't support Mason out-of-the-box just extend the highlighting config. The source of mentioned modul is a good starting point to get syntax infos. Any good editor has to be extendable this way!

UPDATE: maybe helpful: http://osdir.com/ml/ide.komodo.general/2006-05/msg00036.html

(*) which has mason-mode.el extension