url not loading inside iframe in mac-safari and IE9 browsers

hi..
i want to load ebook url inside iframe.
it works in all browsers. except in mac machine safari browser and and IE9 browser ..


how to handle this..
my iframe syntax is:
"iframe runat="server" id="ifrm" style="width: 956px; height: 500px" name="ifrm"


then i load url pro grammatically for the ifraame..
how to handle this..
need ur suggestions with examples


regards
gopal.s