This is the revision history for :utf8 in <freenode.net:##NULL>

factoid_idsubjectcopulapredicateauthornamespace
9085 :utf8 is a PerlIO layer that does NO santity checking whatsoever. It simply sets the SvUTF8 flag. The correct form is :encoding(UTF-8) which -does- perform sanity checking when it reads leonerd <*:##NULL>