What you need to do is to modify the MOSSEditorTools.js
file which can be found in your Program Files\Common Files\Microsoft Shared\web server extensions\wpresources\RadEditorSharePoint\188.8.131.52__1f131a624888eeed\RadControls\Editor\Scripts\7_2_0
folder (the name of the version folder might differ depending on your version).
Add the following function at the end of this file and modify it to suit your needs:
|//change tool's action |
|RadEditorCommandList["InsertDate"] = function(commandName, editor, oTool) |
| //This is the original function. Modify it to match your requirements |
| var now = new Date(); |
| value = " " + now.toLocaleDateString(); |
| editor.PasteHtml(value); |
Reload your page after that and use the new function (you may need to reset IIS first).
the Telerik team