If the remote-outbound-connection disable SSL or add SSL properties that might fail if there are different SSL related properties are overridden by default ones where it should be vice versa. The analysis will be difficult as in EAP6 the failure messages are swallowed. They are only visible in org.jboss.as.ejb3 DEBUG mode.
This issue was verified using the 6.2.0.CR1 preview bits.