I was getting the exact same issue.
When looking at the source code of my pages I found that the gdsr.css.php file generated in the <head> section wasn't loading due to a 500 error.
Upon looking through my error logs I found the following:
[Tue Feb 22 10:59:19 2011] [error] [client 86.160.81.113] SoftException in Application.cpp:601: Directory "/home/uknowotimea$
[Tue Feb 22 10:59:19 2011] [error] [client 86.160.81.113] Premature end of script headers: gdsr.css.php, referer: http://www$
After a bit of research I found that this could be due to the PHP5 handler used in my CPanel/Centos configuration. Changing the PHP5 handler from suphp to dso has resolved the issue and now the stars appear.
Hope the info above helps someone out.