Return key not working for input field

I have a strange problem that I'm having trouble tracking
down any help with.



I've been developing a Flash application with a chat
function. Chat uses a normal text entry field, and, as expected the
user can type into the text entry filed and hit ''return'' or click
Send button to send their message. For some reason, when I'm using
one specific OS X user account, the ''return'' will not submit the
text entry--only clicking the Submit button works.



I've confirmed that other Macs running the same version of
Flash and the same operating system version don't have this
problem. I've even confirmed that other user accounts on the same
computer don't have this problem. Even stranger, the problem exists
in both Firefox and Safari, and it migrated over when I transferred
user data to a new computer. Reinstalling Flash Player and deleting
preference files hasn't helped, and I can't think of a preference
or setting that should affect this.



Anyone have any ideas?