That's rather odd because we've been running these releases for a while now with an issue. Can you tell me what skin you are using? Also, do you have
<add key="AllowMultipleSites" value="true" /> set to true or false in your web.config or user.config? If you have it set to false, please change it to true and let me know if the problem persists.
Final question, which db platform are you using?