Multiple transport Ids?

[Coder One]

Why do we need multiple transportId to refer to a single transport, JMS?  What 
role does the id ".../configuration" play?
 
Thanks....
 
<bean class="org.apache.cxf.transport.jms.JMSTransportFactory"
id="org.apache.cxf.transport.jms.JMSTransportFactory"
lazy-init="true">
<property name="bus" ref="cxf"/>
<property name="transportIds">
<list>
<value>http://cxf.apache.org/transports/jms</value>
<value>http://cxf.apache.org/transports/jms/configuration</value>
</list>
</property>
</bean>