Poor failure message from socket-binding-group add operation

The socket-binding-group add operation does not work. Add operation fails with the error:

11:25:35,087 ERROR [org.jboss.as.controller.management-operation] (management-handler-threads - 8) JBAS014612: Operation ("add") failed - address: ([("socket-binding-group" => "test-sockets")]): org.jboss.msc.service.DuplicateServiceException: Service jboss.socket-binding-manager is already registered
at org.jboss.msc.service.ServiceRegistrationImpl.setInstance(ServiceRegistrationImpl.java:154) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at org.jboss.msc.service.ServiceControllerImpl.startInstallation(ServiceControllerImpl.java:227) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at org.jboss.msc.service.ServiceContainerImpl.install(ServiceContainerImpl.java:560) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at org.jboss.msc.service.ServiceTargetImpl.install(ServiceTargetImpl.java:201) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at org.jboss.msc.service.ServiceControllerImpl$ChildServiceTarget.install(ServiceControllerImpl.java:2228) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]

Steps to reproduce:
1) start standalone server
2) connect via CLI
3)
[standalone@localhost:9999 /] /socket-binding-group=test-sockets:add(default-interface="public")
{
"outcome" => "failed",
"failure-description" => "JBAS014749: Operation handler failed: Service jboss.socket-binding-manager is already registered",
"rolled-back" => true
}