Chris:
I believe that there is cross-browser support for the OnPaste event, but it is handled differently by browsers. See the
onpaste event | paste event reference article for insights.
The alternative approach is defined in the above mentioned
Editor/Cleaning Word Formatting demo:
Formatting can also be stripped automatically on page submit for browsers that do not provide onpaste event using the OnClientSubmit event and FormatStripper command of RadEditor, e.g.
<script type="text/javascript">
function OnClientSubmit(editor)
{
editor.fire("FormatStripper", {value : "WORD"});
}
</script>
<telerik:RadEditor runat="server" OnClientSubmit="OnClientSubmit"/>
Cheers!