ResourceWizard - ConcurrentModificationException

The resource wizard is virtually not working when resource definition contains this code in schemaHandling:

<activation>
<existence>
<outbound>
<expression>
<script>
<code>
import com.evolveum.midpoint.xml.ns._public.common.common_3.ActivationStatusType;

legal && ActivationStatusType.ENABLED == focus.getActivation().getAdministrativeStatus();
</code>
</script>
</expression>
</outbound>
</existence>
</activation>

Way to reproduce:

• Edit resource with wizard
• Click Schema handling tab
• Click Schema tab or go back with Previous button
• Error will appear:

015-11-27 13:47:02,548 [] [http-apr-8080-exec-4] ERROR (com.evolveum.midpoint.web.security.MidPointApplication): Error occurred during page rendering.
org.apache.wicket.WicketRuntimeException: Method onRequest of interface org.apache.wicket.behavior.IBehaviorListener targeted at org.apache.wicket.ajax.markup.html.form.AjaxSubmitLink$1@3e7a2ee6 on component [AjaxSubmitLink [Component id = link]] threw an exception
at org.apache.wicket.RequestListenerInterface.internalInvoke(RequestListenerInterface.java:268) ~[wicket-core-6.20.0.jar:6.20.0]
....

Caused by: java.util.ConcurrentModificationException: null
at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:859) ~[na:1.7.0_80]
at java.util.ArrayList$Itr.next(ArrayList.java:831) ~[na:1.7.0_80]
at com.evolveum.midpoint.web.component.wizard.resource.SchemaHandlingStep.prepareActivation(SchemaHandlingStep.java:966) ~[SchemaHandlingStep.class:na]
at