There is a 10 character minimum when posting messages but you normally shouldn't have a problem editing a longer message.
Without seeing the message or being able to recreate the problem it is hard to say why the forum software thought your message was under 10 characters.
Messages are often edited and so far I've never had any other reports of problems. If you run into this again please post or send me the exact content of the message that was rejected so I can try to recreate the problem.
Don
Good night...