Hello Uros, AS7 has a different way of deploying JDBC drivers than previous AS versions. There are two ways: 1) you simply install your JDBC driver as deployment (put the jar to <as7>/standalone/deployments), or 2) install the driver as a AS7 module. You can find more details here: https://community.jboss.org/wiki/DataSourceConfigurationInAS7.
I have made oracle jdbc connection as module and made datasource for my application deployed on gatein, but still i dont know what causing this problem. i have put a log.txt of stack trace so you can look Tomas. Thanks a lot.