Maven multi module - remove a module

Say I have the setup

aggregator pom
     - module a
     - module b

now module b depends on a for compilation.

Is there a way in the IDE to turn off module a from being built and defaulting out to the repo for a version build / snapshot ??

Using 11.02 and when I remove module a from the project the code stops compiling.

Guess I was expecting it to swap the module dependency for one from the local repo.

Thanks