xpathString = (String)arg;
else
xpathString = StringFunction.evaluate(arg, nav);
try {
XPath xpath = nav.parseXPath(xpathString);
ContextSupport support = context.getContextSupport();
xpath.setVariableContext( support.getVariableContext() );
xpath.setFunctionContext( support.getFunctionContext() );
xpath.setNamespaceContext( support.getNamespaceContext() );
return xpath.selectNodes( context.duplicate() );