Massage is too short?

[heeroyun]

I've just upgraded to vbulletin 3.7.0 a few day ago. Everything seem to be okay. But there is one problem: My members who write a super-long-post and tried to post but there was a error say "The massage you enter is too short. Please lengthen it to at least 5 characters" and as I said, the post was very long. The problem occur with editing and posting with too many character on the post.

Any idea how to solve this problem?

Greatly appriciated