assembly does not honnor <dependencyManagement> directives

My project uses many libs and has <dependencyManagement> set to force commons-logging on version 1.1.1
I still have commons-logging 1.1 in my assembly targ.gz, (with its dependencies : logkit, avalon ...)
Forcing a dependency to commons-logging 1.1.1 solves this, but this is just a workaround.

As the assembly plugin uses "dependencyResolver.resolveDependencies( project, ... " we could expect the dependencyResolver to read the <dependencyManagement>, but this doesn't seem to work as expected.