Deleting the actual content of a post (and its subject) while "! Delete this message !" is checked, then submitting will also return an error. If that particular option is checked we should probably just ignore the contents of the message/subject input. ()

(You can probably just spam empty BBCode tags to get around any kind of word/character limit, so please, bear that in mind if implementing any such checks. The return key shouldn't count towards the minimum, either.)

Sounds like there is a minir bug in the delete post option.