Is there a way i can disable a module in jboss 7.1.2?

our base jboss installation currently is read only with only logs, deployments and configurations being writable. One of the modules that comes with the jboss installation - com.foo.bar needs to be replaced with a different version. I can do that by providing an alternate location for my module and specifying it as a global module in the configuration with a different name com.foo.bar1. But how do i make sure that module that i replaced (com.foo.bar) never gets loaded. i cannot simply delete since it is in a read-only location. if it is simply not referenced anywhere does that mean that it will never get loaded? i want to avoid conflicts since both modules will have the same classes.