If the frame contains page from the same domain (does not violate same-origin policy), you can interact directly with its document:
<script type="text/javascript">
window.onload = function() {
var oFrame = document.getElementById("myframe");
oFrame.contentWindow.document.onclick = function() {
alert("frame contents clicked");
};
};
</script>
If it contains external page then you're out of luck - no way to do what you want for obvious security reasons. Although all the contents is visually parts of the same page, frames coming from different domains must stay separate in terms of scripting. Otherwise any page could e.g. create a hidden iframe loading your webmail and steal your session cookie from it. All the data is accessible to the user, but it should not be accessible to the page author.
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