Talking about this one with Eastlink members right now.  That COA is certainly interesting - the thing is, I don't think it belongs to that album (the other possibility being that it's fabricated altogether). Foremost, the ink looks too fresh for 1985.

http://www.ebay.com/itm/BONO-SIGNED-FRAMED-WAR-ALBUM-AUTOGRAPH-U2-G...

The signature set is quite atypical, and it stood out immediately.  I think these were forgeries using the facsimile example from the U2 by U2 book as a template, shown below.