another user posted a problem similar to yours.
http://www.rejetto.com/forum/index.php/topic,9953.0.htmlafter some investigation what we found was that Chrome (the browser) has a bug with frames.
Frames were introduced by the dynamic dns provider he was using.
Anyway this problem was reported only on Chrome. Are you using Chrome or a different browser?
Moreover, frames were introduced only in a specific configuration of the dns. The standard service (IIRC) doesn't.
If your case is the same, then it's not an HFS' fault.