I have an remote service (ProjectService) which looks (somewhat) like this: import com.domain.Project interface ProjectService { Project get(Long id) void store(Project project) } When using httpinvoker, the first request works. I supply the id, and the Project nicely gets transfered. However, when I to use the store method, the transfer fails, and I get a ClassNotFoundException: org.springframework.web.util.NestedServletException: Class not found during deserialization; nested exception is java.lang.ClassNotFoundException: com.domain.Project. the complete stacktrace looks like this:. [72985] errors.GrailsExceptionResolver Class not found during deserialization; nested exception is java.lang.ClassNotFoundException: com.domain.Project org.springframework.web.util.NestedServletException: Class not found during deserialization; nested exception is java.lang.ClassNotFoundException: com.domain.Project at org.springframework.remoting.httpinvoker.HttpInvokerServiceExporter.handleRequest(HttpInvokerServiceExporter.java:78) at org.springframework.web.servlet.mvc.HttpRequestHandlerAdapter.handle(HttpRequestHandlerAdapter.java:49) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:875) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:809) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:571) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:511) at javax.servlet.http.HttpServlet.service(HttpServlet.java:727) at javax.servlet.http.HttpServlet.service(HttpServlet.java:820) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:487) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1098) at org.codehaus.groovy.grails.web.mapping.filter.UrlMappingsFilter.processFilterChain(UrlMappingsFilter.java:157) at org.codehaus.groovy.grails.web.mapping.filter.UrlMappingsFilter.doFilterInternal(UrlMappingsFilter.java:148) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1089) at org.codehaus.groovy.grails.web.sitemesh.GrailsPageFilter.parsePage(GrailsPageFilter.java:123) at org.codehaus.groovy.grails.web.sitemesh.GrailsPageFilter.doFilter(GrailsPageFilter.java:86) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1089) at org.codehaus.groovy.grails.web.servlet.mvc.GrailsWebRequestFilter.doFilterInternal(GrailsWebRequestFilter.java:65) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1089) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:236) at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1089) at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:365) at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181) at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:712) at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:405) at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:139) at org.mortbay.jetty.Server.handle(Server.java:295) at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:503) at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:841) at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:639) at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:210) at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:379) at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:361) at org.mortbay.thread.BoundedThreadPool$PoolThread.run(BoundedThreadPool.java:442) Caused by: java.lang.ClassNotFoundException: com.domain.Project at org.codehaus.groovy.tools.RootLoader.findClass(RootLoader.java:146) at java.lang.ClassLoader.loadClass(ClassLoader.java:306) at org.codehaus.groovy.tools.RootLoader.loadClass(RootLoader.java:118) at java.lang.ClassLoader.loadClass(ClassLoader.java:251) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:242) at java.io.ObjectInputStream.resolveClass(ObjectInputStream.java:585) at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1544) at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1466) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1699) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1305) at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1634) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1299) at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1908) at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1832) at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1719) at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1305) at java.io.ObjectInputStream.readObject(ObjectInputStream.java:348)