Resizing of frame with DYNAMIC external source [on hold]

Normal page structure :-

<body>
    <div>
        blah blah
    </div>
    <iframe>
        this is an iframe whose source is modified frequently and point to various domains. This needs to be resized dynamically according to the src page it points to right now ....
    </iframe>
</body>

I tried many codes, including the “contentWindow…..scrollHeight” thing, but as it is an external frame, the brower blurts something like “Security warning. access to frame with external frame not allowed ”

Read somewhere that this can be accomplished using framesets ?

Any help will be highly appreciated.

Resizing of frame with DYNAMIC external source [on hold]