Yes, it is.
I made some minor changes to the original code. I centered the image, and added a check to ensure it doesn't show up if a user did not specify a date of birth (in my case, I did an import, and for some reason ended up with users displaying the word "zodiac_" instead of an image).
Code:
<div class="usericons">
<xen:if is="{$message.zodiac_sign}"><center><img src="styles/default/zodiac/{$message.zodiac_sign}.gif" alt="{$message.zodiac_sign_label}" title="{$message.zodiac_sign_label}" /></center></xen:if>
</div>
Thanks for the Add-On