When the smiley (smile) is used, it will choose a random smile from all of the existing xat smiles, including powers you do not have.
If a smiley belonging to a power you do not have is chosen, then only the code will be displayed, not the actual smiley.
If you want to use the regular smile smiley, you have to type all of the letters in uppercase (SMILE).
If you type multiple (smile) into one message, only the last smile will be replaced.
If you add text after a (smile), then the smiley will not be replaced. You can, however, add text before the (smile).