<plugin>
   <extension point="com.ibm.team.repository.common.linkTypes">
      <linkType
              constrained="true"
            id="de.rtc.extensions.linktypes.workitemLink"
            internal="false">
         <source>
            <endpoint multiplicity="0..1" displayName="SourceWorkitem">
               <itemReferenceType
                     itemTypeName="WorkItem"
                     packageURI="com.ibm.team.workitem">
               </itemReferenceType>
            </endpoint>
         </source>
         <target >
            <endpoint multiplicity="0..1" displayName="TargetWorkitem">
               <itemReferenceType
                     itemTypeName="WorkItem"
                     packageURI="com.ibm.team.workitem">
               </itemReferenceType>
            </endpoint>
         </target>
      </linkType>
   </extension>
</plugin>