Comparing two macros

[jblocksom]

I have two macros, call them A and B, with strings in them and I want a group to run only if they are not equal. I can't figure out how to get that right. In the conditional build rule, I have the macro/expression field set to
%A% <> %B%
and the condition set to is true. This skips it every time. If I enclose the expression in square brackets, it gives a macro error. What is the trick to this?