NPE when modifying an existing server-group scoped role

{
    "operation" => "composite",
    "address" => [],
    "steps" => [
        {
            "address" => [
                ("core-service" => "management"),
                ("access" => "authorization"),
                ("server-group-scoped-role" => "main-DEPLOYER")
            ],
            "name" => "base-role",
            "value" => "MAINTAINER",
            "operation" => "write-attribute"
        },
        {
            "address" => [
                ("core-service" => "management"),
                ("access" => "authorization"),
                ("server-group-scoped-role" => "main-DEPLOYER")
            ],
            "name" => "server-groups",
            "value" => ["main-server-group"],
            "operation" => "write-attribute"
        }
    ]
}

17:23:59,102 ERROR [org.jboss.as.controller.management-operation] (host-controller-connection-threads - 1) JBAS014612: Operation ("write-attribute") failed - address: ([
    ("core-service" => "management"),
    ("access" => "authorization"),
    ("server-group-scoped-role" => "main-DEPLOYER")
]): java.lang.NullPointerException
	at org.jboss.as.controller.access.constraint.ServerGroupEffectConstraint.setAllowedGroups(ServerGroupEffectConstraint.java:108) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.access.constraint.ServerGroupEffectConstraint.setAllowedGroups(ServerGroupEffectConstraint.java:108) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.domain.management.access.ServerGroupScopedRoleWriteAttributeHandler.applyChangeToConstraint(ServerGroupScopedRoleWriteAttributeHandler.java:78) [wildfly-domain-management-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.domain.management.access.ServerGroupScopedRoleWriteAttributeHandler.applyUpdateToRuntime(ServerGroupScopedRoleWriteAttributeHandler.java:55) [wildfly-domain-management-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.AbstractWriteAttributeHandler$1.execute(AbstractWriteAttributeHandler.java:101) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.AbstractOperationContext.executeStep(AbstractOperationContext.java:609) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.AbstractOperationContext.doCompleteStep(AbstractOperationContext.java:487) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.AbstractOperationContext.completeStepInternal(AbstractOperationContext.java:277) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.AbstractOperationContext.executeOperation(AbstractOperationContext.java:272) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.ModelControllerImpl.internalExecute(ModelControllerImpl.java:258) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.ModelControllerImpl.execute(ModelControllerImpl.java:143) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.remote.TransactionalProtocolOperationHandler.internalExecute(TransactionalProtocolOperationHandler.java:218) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.remote.TransactionalProtocolOperationHandler$ExecuteRequestHandler.doExecute(TransactionalProtocolOperationHandler.java:130) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.remote.TransactionalProtocolOperationHandler$ExecuteRequestHandler$1.run(TransactionalProtocolOperationHandler.java:109) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.remote.TransactionalProtocolOperationHandler$ExecuteRequestHandler$1.run(TransactionalProtocolOperationHandler.java:105) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at java.security.AccessController.doPrivileged(Native Method) [rt.jar:1.7.0_17]
	at javax.security.auth.Subject.doAs(Subject.java:356) [rt.jar:1.7.0_17]
	at org.jboss.as.controller.remote.TransactionalProtocolOperationHandler$GetSubjectResponseHandler$1$1.run(TransactionalProtocolOperationHandler.java:196) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.controller.remote.TransactionalProtocolOperationHandler$GetSubjectResponseHandler$1$1.run(TransactionalProtocolOperationHandler.java:192) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at java.security.AccessController.doPrivileged(Native Method) [rt.jar:1.7.0_17]
	at org.jboss.as.controller.remote.TransactionalProtocolOperationHandler$GetSubjectResponseHandler$1.execute(TransactionalProtocolOperationHandler.java:192) [wildfly-controller-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.protocol.mgmt.AbstractMessageHandler$2$1.doExecute(AbstractMessageHandler.java:296) [wildfly-protocol-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at org.jboss.as.protocol.mgmt.AbstractMessageHandler$AsyncTaskRunner.run(AbstractMessageHandler.java:518) [wildfly-protocol-8.0.0.Beta1-SNAPSHOT.jar:8.0.0.Beta1-SNAPSHOT]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [rt.jar:1.7.0_17]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [rt.jar:1.7.0_17]
	at java.lang.Thread.run(Thread.java:722) [rt.jar:1.7.0_17]
	at org.jboss.threads.JBossThread.run(JBossThread.java:122) [jboss-threads-2.1.1.Final.jar:2.1.1.Final]