Duplicate keys in model -- Host controller complains

Host controller complains sometimes

[Host Controller] 14:38:03,748 ERROR [org.jboss.as.domain.http.api] (HttpManagementService-threads - 2) JBAS015100: Unexpected error executing model request: org.jboss.as.controller.OperationFailedRuntimeException: JBAS014662: Duplicate path element 'server' found [ "JBAS014662: Duplicate path element 'server' found" ]

Enabling check for dups in RHQ shows that one culprit is the runtime info on mail

[domain@localhost:9999 mail-session=java:jboss/mail/Default] :read-children-types
{
"outcome" => "success",
"result" => ["server"]
}
[domain@localhost:9999 mail-session=java:jboss/mail/Default] pwd
/host=master/server=server-one/subsystem=mail/mail-session=java:jboss/mail/Default

[10:51:50] <pilhuhn> [domain@localhost:9999 mail-session=java:jboss/mail/Default] pwd
[10:52:23] <pilhuhn> here the child-type from a mail-session is named "server", which collides with the /host=x/server=y key