How can I add the Party smiley to my conversations?
Go, Shawty, it’s your birthday. We’re gonna party like it’s your birthday. We’re gonna sip Bacardi like it’s your birthday. But do you know how we add this f*cking smiley? 
Since MSN Messenger 6.2 your shortcut codes are automatically replaced with corresponding emoticons while you’re typing. Because of this new feature, users can not use the <:o) shortcut for Party smile anymore because it will get replaced with the surprised smiley 
). Here’s how to add it to your conversation:
a) You will have to select it from the emoticons shortcut list (in MSN Messenger 7, you can Pin it so the smiley always appears in the list)
b) Or type <o) and then add the : before the o.
Party on!