I have seen this one before but I can't find the post right now (if it was a post... may have just been someone who asked me on MSN).
Basically, we've all seen cases where the UV ink is weaker or stronger than other notes, particularly with the presecurity notes. This may simply be a case of the ink being extremely weak. I also believe that at least with the presecurity notes, that UV ink wasn't as durable as the new red and yellow ink, thus with circulation and/or time, the ink "wore off" to some degree.
Also to note, it should be well known that various security features can be removed without a trace with common household cleaning supplies. In particular, the gold leaves can be easily removed. It is my suspicion that the blue UV ink is a similar case.
I have enough doubt about the authenticity of this "error" to not get too excited about it.
Logged
BWJM, F.O.N.A.
Life Member of CPMS, RCNA, ONA, ANA, IBNS, WCS.
President, IBNS Ontario Chapter.
Treasurer, Waterloo Coin Society.
Show Chair, Cambridge Coin Show.
Fellow of the Ontario Numismatic Association.