selectionFailure issue : no initialization when declaring variables

In BPEL excecution, can't get over copy in assign due to selectionFailure;
Cause : initialization is not done when variables are declared.

Extracts of the BPEL code :

<scope name="ScopeWs">
<variables>
<variable name="Out" xmlns:tns="http://dolmen.ft.fr/" messageType="tns:Response"/>
<variable name="In" xmlns:tns="http://dolmen.ft.fr/" messageType="tns:Request"/>
</variables>
<sequence name="SequenceWs">

<assign name="Assign">
<copy>
<from variable="bpelId"/>
<to>$In.parameters/Id</to>
</copy>
</assign>
<invoke name="Invoke" partnerLink="WsPartnerLink" operation="invoke" xmlns:tns="http://dolmen.ft.fr/" portType="tns:Ws" inputVariable="In" outputVariable="Out"/>
</sequence>
</scope>

Error :

INFO [ASSIGN] Assignment Fault:

{http://docs.oasis-open.org/wsbpel/2.0/process/executable}

selectionFailure,lineNo=86,faultExplanation=No results for expression:

{OXPath10Expression $In.parameters/Id}

Patches for ODE are available : https://issues.apache.org/jira/browse/ODE-915
Could it be possible to integrate theses patches to the latest version of Riftsaw ?
We can't get our application of 200+ BPEL working without this.