Language has been deprecated in favor of type, and the language for the value of the intrinsic event should be defined in a meta declaration.
Code:
<meta http-equiv="Content-Script-Type" content="text/javascript">
<script type="text/javascript">
function foo() {
}
</script>

<p><a href="going_here_if_no_js.html" onclick="foo(); return false">click me</a></p>