This is with jaybird 2.2.5 JDK 7. I use JBoss App server 4.2.3 on JDK 1.7.0-40

My datasource definition is:

<?xml version="1.0" encoding="UTF-8"?>
<connection-factories>
  <tx-connection-factory>
    <jndi-name>DSoftDS</jndi-name>
    <xa-transaction/>
    <track-connection-by-tx/>
    <rar-name>jaybird-2.2.5.rar</rar-name>
    <connection-definition>javax.sql.DataSource</connection-definition>
    <config-property name="Database" type="java.lang.String">localhost/3050:powerpro_clean</config-property>
    <user-name>sysdba</user-name>
    <password>masterkey</password>
    <config-property name="Encoding">UNICODE_FSS</config-property>
    <min-pool-size>5</min-pool-size>
    <max-pool-size>100</max-pool-size>
      <metadata>
         <type-mapping>PowerPro</type-mapping>
      </metadata>
  </tx-connection-factory>
</connection-factories>

this works without problem with  Jaybird 2.1.6. I see the only difference in the code path is that there is an extra check in AbstractConnection.setAutoCommit that checks is this connection is part of distributed transaction and triggers this error.

If I don't call close I get error message that connection was closed for me when transaction was committed.