weird error in firebug when using youtube content

[GKATZ]

Hi;
when using youtube content there is a weird error exactly at the time that the content is loaded into the frame. the error states: "Permission denied to call method Location.toString"

it happens right after this line 98 in the iframe player ("win.location = this.obj.content; // set the iframe's location") and it happens also in shadow box distribution in the index.html when the youtube movie is clicked.
 note that everything works fine even though the error is raised in firebug... and also, it might be something related to firebug 1.2 + FF3 but i thought is was worth mentioning.
here is a print screen:


how can I fix this?
thanks.