OSM SOAP Data Provider and Model Variables

Hello,

I was wondering if it would be possible to use model variables to configure the Input Parameters of the WebService Data Provider: for example for different environments the endpoint could be different.

I've tried using this value for soap.endpoint: '%{SOAP_ENDPOINT}' (with Expression = XPATH and also XQUERY) and I get the following error:

<19-Nov-2015 12:50:00,743 GMT PM> <ERROR> <impl.BaseExternalInstanceContainer> <[ACTIVE] ExecuteThread: '3' for queue: 'weblogic.kernel.Default (self-tuning)'> <failed to invoke adapter for externalInstanceType: name[MobileCatalogDataInstance] class[com.mslv.oms.view.rule.adapter.SOAPAdapter]>

java.lang.IllegalArgumentException: Malformed escape pair at index 0: %{SOAP_ENDPOINT}