John,
> For some reason, when someone visits the www.domain_name.com and clicks in
> the second iframe it tries to access the main (top) page through
> domain_name.com instead, and this creates an error:
>
> Error Line 30
> Permission Denied.
You might look into the document.domain property [1] to see whether that
will solve your problem.
James Aylard
1.
http://developer.netscape.com/docs/manuals/js/client/jsref/document.htm#1193
628,
http://msdn.microsoft.com/workshop/author/dhtml/reference/properties/domain.
asp