JBoss classloading model is flat, this means that all apps in deploy dir can eventually 'see' each other.
I think you don't need to put the same classes that are used in your common Spring module into each separate app (you just need them when compiling). Try w/o.
But be sure Spring common module is deployed before the two other web apps.
Thank you for this answer. I'll try it, and give you feedback as soon as possible