Having upgraded seam 1.2.1GA project to Seam 2 and JBoss EAP 4.2; my project is now unusable. I can't seen to find out why I get the following error and where it comes from. On some pages it occurs when html form is submitted, and on some just when page is being displayed?

Seam 2.0GA + Facelets + Sun RI. I followed Seam2Migration instructions.

0:28:58,516 ERROR [SeamPhaseListener] uncaught exception
javax.el.ELException: java.lang.IllegalArgumentException: argument type mismatch
 at javax.el.BeanELResolver.setValue(BeanELResolver.java:116)
 at javax.el.CompositeELResolver.setValue(CompositeELResolver.java:68)
 at com.sun.faces.el.FacesCompositeELResolver.setValue(FacesCompositeELResolver.java:93)
 at org.jboss.el.parser.AstPropertySuffix.setValue(AstPropertySuffix.java:73)
 at org.jboss.el.parser.AstValue.setValue(AstValue.java:84)
 at org.jboss.el.ValueExpressionImpl.setValue(ValueExpressionImpl.java:249)
 at org.jboss.seam.core.Expressions$1.setValue(Expressions.java:117)
 at org.jboss.seam.navigation.Pages.applyConvertedValidatedValuesToModel(Pages.java:779)
 at org.jboss.seam.navigation.Pages.postRestore(Pages.java:402)
 at org.jboss.seam.jsf.SeamPhaseListener.postRestorePage(SeamPhaseListener.java:528)
 at org.jboss.seam.jsf.SeamPhaseListener.afterRestoreView(SeamPhaseListener.java:374)
 at org.jboss.seam.jsf.SeamPhaseListener.afterServletPhase(SeamPhaseListener.java:211)
 at org.jboss.seam.jsf.SeamPhaseListener.afterPhase(SeamPhaseListener.java:184)
 at com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:280)
 at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:117)
 at javax.faces.webapp.FacesServlet.service(FacesServlet.java:244)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:83)
 at org.jboss.seam.web.MultipartFilter.doFilter(MultipartFilter.java:85)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.jboss.seam.web.ExceptionFilter.doFilter(ExceptionFilter.java:64)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.jboss.seam.web.RedirectFilter.doFilter(RedirectFilter.java:44)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.ajax4jsf.webapp.BaseXMLFilter.doXmlFilter(BaseXMLFilter.java:141)
 at org.ajax4jsf.webapp.BaseFilter.doFilter(BaseFilter.java:281)
 at org.jboss.seam.web.Ajax4jsfFilter.doFilter(Ajax4jsfFilter.java:60)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.jboss.seam.web.LoggingFilter.doFilter(LoggingFilter.java:58)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.jboss.seam.debug.hot.HotDeployFilter.doFilter(HotDeployFilter.java:68)
 at org.jboss.seam.servlet.SeamFilter$FilterChainImpl.doFilter(SeamFilter.java:69)
 at org.jboss.seam.servlet.SeamFilter.doFilter(SeamFilter.java:158)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
 at org.jboss.web.tomcat.filters.ReplyHeaderFilter.doFilter(ReplyHeaderFilter.java:96)
 at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
 at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
 at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230)
 at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
 at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:179)
 at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:433)
 at org.jboss.web.tomcat.security.JaccContextValve.invoke(JaccContextValve.java:84)
 at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
 at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
 at org.jboss.web.tomcat.service.jca.CachedConnectionValve.invoke(CachedConnectionValve.java:157)
 at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:543)
 at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
 at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:241)
 at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
 at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:580)
 at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
 at java.lang.Thread.run(Thread.java:619)
Caused by: java.lang.IllegalArgumentException: argument type mismatch
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
 at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
 at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
 at java.lang.reflect.Method.invoke(Method.java:597)
 at javax.el.BeanELResolver.setValue(BeanELResolver.java:108)
 ... 53 more
00:28:58,532 ERROR [CachedConnectionValve] Application error: Faces Servlet did not complete its transaction