I only found this similar bug https://issues.jboss.org/browse/AS7-1283, but apparently it should be fixed in 7.0.1. Can anyone confirm it is working in 7.1.1?
On the other hand I tried the WA specified in the issue, but there is no change in behavior so I suspect that my case is something different. Anyway, there's not much I can do except for wait / search further :)