PHP Error

The lightbox works great but I'm getting an error message on the page. How do I fix this so the message goes away?
Link to the site: mountaingemsconifer.com/index.php

Strict Standards: Only variables should be assigned by reference in /home/mountgem/public_html/modules/mod_hot_lightbox/tmpl/default.php on line 15

Thank you

You site is totally down, I get 404 NOT FOUND when I browse link.
About problem this might help:
Go to joomla global configuration server tab and level down error reporting level.