named data ranges

Hello again
I appear to be experiencing a problem with named data ranges lo 5.2.2.2 x64 win 7.

Q. Is it possible and permissible to define overlapping data ranges? I want a range named mdec which will be A1:B25 and another xlit B1:C25 (the col B values are common) to use in lookups.

I have set them up and they appear ok in the Define Database Range dialog. However, when i try to enter xlit as the range in a formula i find that it automatically gets changed to mdec.

Im going now to try with the ranges defined explicitly instead of using the names, but i wonder if this problem sounds at all familiar to anyone, and if theres anything i can do about it?

Thanks
Gary