Comment 1 for bug 708029

I have confirmed this behaviour, and agree that it would be nice to offer some defensive programming to prevent it.

The problem is the authority_tag_map that includes the 4xx fields, which doesn't really make sense in either a bibliographic record or authority record context.

I have committed r19334 to trunk to remove the 4xx fields from the authority tag map and will backport that fix to 2.0.1.