Saved mapping not showing field if field+group name length too long

I have been trying to figure why some Saved Mappings don't display some field labels when reused.

It relates to the combined length of the Field Name and the Field Group Name

ie the following does get reloaded when using the saved mapping

testing length of field a :: TEST PD length of field for import

but this does not

testing length of field abcd :: TEST PD length of field for import

but if I then change this back to the shorter version, the Saved Mapping show the field label without my having to reset it.

So I think that the Mapping is saving the field label, but that when reusing the mapping, it won't load any that are, my guess, over 64 characters in combined length.

Have proved this on DEMO with the above settings.

Described as above here - http://forum.civicrm.org/index.php/topic,14343