unclear validation error message for unknown attribute?

hi,

 I have an instance document which contains something like

        <TAG myattr="foo"/>

and declares itself against a DTD which does not declare the myattr
attribute.

I get a legitimate validation error when this is detected, but imho its
far from clear from the error message:

        Attribute "myattr" must be declared for element type "TAG".

I've had a quick search in the bug database and could not find anything
that logs this, would it be reasonable to put in an enhancement request?

thanks,
Andrew