Bigger subject in Picture Messages?

Recently I've looked into TwitPic's API and they have a unique email address you can send a picture message to and they'll update your twitter status with a link to that picture. You can add text to the status message if you write it in the subject line. Problem is, on the Behold, if you add a subject line, it limits you to 40 characters, hardly enough to update a twitter status. Using TK Explorer, is there a place where I can adjust that number to 140? Or at least 100?