I have a Maven project depending on couple other Maven projects. I am using Spring 3.1.1 in my project and dependent projects have 3.0.6. I am trying to exclude Spring 3.0.6
Your dependency type is war so there is no resolution happening here. Maven overlays the war contents over your project.
When the war is published to repository, the artifact will contain dependent libraries in WEB-INF lib folder. During overlay it does not treat lib folder any different from any static resource unless you tell it to exclude in different way.Check 'overlay' property here