I've encountered a related problem in ActiveState Perl 5.8.6 (see Re^2: Attribute confusion). I posted a bug report, but haven't pursued it further. The error msg reported there might be a clue as to the cause, tho its interesting that newer versions seem to suppress the error msgs.

IIRC, I tried to diagnose the Attributes::Handler code, but got lost pretty quickly in some of its more arcane symbol twiddling.