I have a ubuntu 12.04 LTS installation running and when i copy cmdbuild.war to my webapps folder, cmdbuild works just fine, however when i copy cmdbuild-shark-server to the webapps folder tomcat suddenly refuses to listen on 8080, stating that the address is already in use.
So i took a gamble and disabled ipv6. Result: it works.
Any hints from Technota?