REST MockResponse can't access requestContent

I'm trying to get my REST MockResponse to return a response based on the input criteria.The issue i'm seeing however is that this line of SCRIPT fails:
def holder = new com.eviware.soapui.support.XmlHolder( mockRequest.requestContent )



When I run the mockRequest against this response the error is returned as:

ERROR:com.eviware.soapui.impl.wsdl.mock.DispatchException: com.eviware.soapui.impl.wsdl.mock.DispatchException: Failed to dispatch using script; groovy.lang.GroovyRuntimeException: Ambiguous method overloading for method com.eviware.soapui.support.XmlHolder#<init>.
Cannot resolve which method to invoke for [null] due to overlapping prototypes between:
[interface org.apache.xmlbeans.XmlObject]
[interface org.w3c.dom.Node]
com.eviware.soapui.impl.wsdl.mock.DispatchException: com.eviware.soapui.impl.wsdl.mock.DispatchException: Failed to dispatch using script; groovy.lang.GroovyRuntimeException: Ambiguous method overloading for method com.eviware.soapui.support.XmlHolder#<init>.
Cannot resolve which method to invoke for [null] due to overlapping prototypes between:
[interface org.apache.xmlbeans.XmlObject]
[interface org.w3c.dom.Node]

There's no documentation that i can see to assist with this error? Has anyone seen this and resolved?