Question on javascript onClick insert into text area

Okay, I want to do something like this message box has... with the smilies where you click them and then the code for them appears in the text area... I tried deciphering the source but there's so much else going on that I was pretty much lost, so how would I get a smilie list that when clicked inserts the smilie symbol into the text area at the end of the message?

http://www.codingforums.com/showthread.php?t=34604

hehe *blush* much thanks... I did do a search... apparently too detailed of keywords :-P Thanks a bunch :-)