Webmail AD Blocker is an add-on for Internet Explorer. With Webmail AD Blocker, all ADs of webmail(Yahoo mail, Hotmail, Gmail) will be removed. You can then use your webmail without disturbing of ADs.
Changing the div.ch to div.rh seems to work for me. Quick bit of developer toolbar will get you the id for the ads (information -> Display id & class, Outline -> Outline block level elements)
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