You can, but most editors will mess it up. The trick is to add the JS in HTML view and then save the content. If the editor doesn't get a chance to reformat the code, it will usually be correctly persisted.
I got fed-up with doing this and in NukeHTML I added a JS block in the module's context menu where JS can be entered. This is an easy mod to make to the Text/HTML module if you find yourself needing to do it often.
Nik Kalyani
Speerio, Inc.
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