Problem is solved now. The reason for this multiple calls was my login module.Due to the fact that my application was migrated from an OC4J application server, my custom login module class simply implemented the LoginModule interface so the option for password stacking was useless. After changing the login module so it will extend JBoss's UsernamePasswordLoginModule the cache begin to work. So for me this issue is resolved in 7.1.2 release.
Thank you,
Daniel