The solution was simply to take the protocol outside the formPanel and use "protocol.options.url = newUrl;", simple like that! -- View this message in context: http://osgeo-org.1560.n6.nabble.com/replace-protocol-in-geoext-form-formpanel-tp5027505p5034365.html Sent from the OpenLayers Users mailing list archive at Nabble.com.