Problem:  The AIM Instant Message window limits you from sending anything more then 1024 characters.  This means if you want to paste a long story, IM conversations, or an IM that contains lots of hidden html tags (bold words, colored text all takes up extra characters) you will get the error message displayed above.

Solution: To get rid of the character paste limit, you need to Directly Connect to your buddy.  This is done by clicking on the "Connect to Send IM Image" icon in the IM window toolbar:

Once you and your buddy have established a Direct Connection, there will no longer be a character paste limitation.