content validation reports that multi select requires -1 entries when number of entries is set to unlimited

Issue Summary

I am experimenting with using the multi-select module to select terms from a hierarchical taxonomy vocabulary (regions / countries of the world).

I need for the content creators to be able to select one or more regions (ie Europe, north America, Asia) and one or more countries in a selected region.

I have also been experimenting with Hierarchical select and wonder if there is a potential conflict when both use the same vocabulary.

I have tried removing both modules and reinstalling them separately and together. still no joy in mudville

any thought would be appreciated.