Hi everybody, I m beginner in Jboss.

I'm doing some exercises, now I m trying to enable the xa-datasource, but it can't enable and show following error message.

Unexpected HTTP response: 500

Request
{
    "xa-datasource-class" => "org.postgresql.xa.PGXADataSource",
    "pad-xid" => false,
    "wrap-xa-resource" => false,
    "same-rm-override" => false,
    "interleaving" => true,
    "name" => "PostgresXA",
    "password" => "password",
    "driver-name" => "postgresql-8.4-703.jdbc4.jar",
    "enabled" => false,
    "user-name" => "postgres",
    "security-domain" => "",
    "jndi-name" => "java:jboss/PostgresXA",
    "pool-name" => "",
    "transaction-isolation" => "TRANSACTION_READ_COMMITTED",
    "new-connection-sql" => "",
    "connection-url" => "",
    "driver-class" => "",
    "valid-connection-checker-class-name" => "",
    "check-valid-connection-sql" => "select 1 from principals",
    "background-validation" => false,
    "background-validation-millis" => 60000L,
    "validate-on-match" => false,
    "stale-connection-checker-class-name" => "",
    "exception-sorter-class-name" => "",
    "prepared-statements-cache-size" => -1L,
    "share-prepared-statements" => false,
    "use-ccm" => false,
    "operation" => "enable",
    "address" => [
        ("profile" => "ha"),
        ("subsystem" => "datasources"),
        ("xa-data-source" => "PostgresXA")
    ]
}

Response

Internal Server Error
{
    "outcome" => "failed",
    "result" => undefined,
    "failure-description" => "JBAS010839: Operation failed or was rolled back on all servers.",
    "rolled-back" => true,
    "server-groups" => {"main-server-group" => {"host" => {"master" => {"server-one" => {"response" => {
        "outcome" => "failed",
        "failure-description" => "JBAS010453: Data-source.xa-config-property service [service jboss.xa-data-source-config.PostgresXA.xa-datasource-properties.portNumber] is already started",
        "rolled-back" => true
    }}}}}}
}

what is the problem.

thank you