[jQuery] Modify head-tag's content in iframe document with IE

Hi,

I get a document in iframe with IE with this:
frame = $doc.frames['myframe'];
frameDocument = frame.document;

and it works correctly.

but how can I get head tag to modify its content?
this doesn't work:

var heads = frameDocument.getElementsByTagName("head");
$(heads).append("<link rel='stylesheet' type='text/css'
href='selector.css' />");

Thanks,
Julio