Having recently upgraded a project from ZK R6 to R6.02 I've detected a bug with having a checkbox element in a grid template.

<grid id="scenarios"
model="@load(vm.scenarioModel)
@save(vm.scenarioModel,before='compareScenarios')">
<auxhead>
<auxheader colspan="4">
<button label="Compare scenarios" disabled="@load(vm.cannotCompare)" onClick="@command('compareScenarios')"/>
<space />
<button label="Change existing scenarios" />
<space />
<button label="Add new scenario" onClick="@command('addScenario')"/>
</auxheader>
</auxhead>
<columns>
<column label="Compare" width="90px" align="center"/>
<column label="Scenario name" />
<column label="Links" />
<column label="Evaluation state" />
</columns>
<template name="model" var="item">
<row>
<checkbox check="@bind(item.selected)" onCheck="@command('selectionChange',state=self.checked, scenarioID=item.ID)"/>
<a label="@load(item.title)" />
<a label="@load(item.links)" />
<a label="@load(item.evaluationState)" />
</row>
</template>
</grid>

Take out the check="@bind(item.selected)" attribute setting and it works fine in R6.0.2. This code worked fine in R6.

The following error is reported:
19-Sep-2012 06:02:33 org.zkoss.zk.ui.impl.UiEngineImpl handleError:1351
SEVERE: >>org.zkoss.zel.PropertyNotFoundException: Property 'check' not found on type org.zkoss.zul.Checkbox
>> at org.zkoss.zel.BeanELResolver$BeanProperties.get(BeanELResolver.java:304)
>> at org.zkoss.zel.BeanELResolver$BeanProperties.access$400(BeanELResolver.java:255)
>> at org.zkoss.zel.BeanELResolver.property(BeanELResolver.java:429)
>> at org.zkoss.zel.BeanELResolver.getType(BeanELResolver.java:115)
>> at org.zkoss.zel.CompositeELResolver.getType(CompositeELResolver.java:131)
>> at org.zkoss.zel.CompositeELResolver.getType(CompositeELResolver.java:131)
>> at org.zkoss.xel.zel.XelELResolver.getType(XelELResolver.java:95)
>> at org.zkoss.zel.impl.parser.AstValue.setValue(AstValue.java:210)
>> at org.zkoss.zel.impl.ValueExpressionImpl.setValue(ValueExpressionImpl.java:256)
>> at org.zkoss.xel.zel.ELXelExpression.setValue(ELXelExpression.java:50)
>> at org.zkoss.bind.impl.BindEvaluatorXImpl.setValue(BindEvaluatorXImpl.java:50)
>> at org.zkoss.bind.impl.LoadPropertyBindingImpl.load(LoadPropertyBindingImpl.java:81)
>> at org.zkoss.bind.impl.PropertyBindingHandler.doLoadBinding(PropertyBindingHandler.java:171)
>> at org.zkoss.bind.impl.PropertyBindingHandler.doLoad(PropertyBindingHandler.java:372)
>> at org.zkoss.bind.impl.BinderImpl.loadComponentProperties(BinderImpl.java:1800)
>> at org.zkoss.bind.impl.BinderImpl.loadComponent(BinderImpl.java:1777)
>> at org.zkoss.bind.impl.BinderImpl.loadComponent(BinderImpl.java:1780)
>> at org.zkoss.bind.tracker.impl.BindUiLifeCycle$1.onEvent(BindUiLifeCycle.java:69)
>> at org.zkoss.zk.ui.AbstractComponent.onEvent(AbstractComponent.java:2736)
>> at org.zkoss.zk.ui.AbstractComponent.service(AbstractComponent.java:2685)
>> at org.zkoss.zk.ui.AbstractComponent.service(AbstractComponent.java:2648)
>> at org.zkoss.zk.ui.impl.EventProcessor.process(EventProcessor.java:136)
>> at org.zkoss.zk.ui.impl.UiEngineImpl.processEvent(UiEngineImpl.java:1709)
>> at org.zkoss.zk.ui.impl.UiEngineImpl.process(UiEngineImpl.java:1494)
>> at org.zkoss.zk.ui.impl.UiEngineImpl.execNewPage0(UiEngineImpl.java:463)
>> at org.zkoss.zk.ui.impl.UiEngineImpl.execNewPage(UiEngineImpl.java:316)
>> at org.zkoss.zk.ui.http.DHtmlLayoutServlet.process(DHtmlLayoutServlet.java:215)
>> at org.zkoss.zk.ui.http.DHtmlLayoutServlet.doGet(DHtmlLayoutServlet.java:135)
>> at javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
>> at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
>> at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
>> at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
>> at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:654)
>> at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:445)
>> at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:379)
>> at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:292)
>> at org.zkoss.web.servlet.Servlets.forward(Servlets.java:837)
>> at org.zkoss.zk.ui.http.ExecutionImpl.forward(ExecutionImpl.java:277)
>> at org.zkoss.zk.ui.http.ExecutionImpl.forward(ExecutionImpl.java:286)
>> at org.zkoss.zk.ui.impl.UiEngineImpl.execNewPage0(UiEngineImpl.java:392)
>> at org.zkoss.zk.ui.impl.UiEngineImpl.execNewPage(UiEngineImpl.java:316)
>> at org.zkoss.zk.ui.http.DHtmlLayoutServlet.process(DHtmlLayoutServlet.java:215)
>> at org.zkoss.zk.ui.http.DHtmlLayoutServlet.doGet(DHtmlLayoutServlet.java:135)
>> at javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
>> at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
>> at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
>> at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:368)
>> at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:109)
>> at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:83)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
>> at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:97)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
>> at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:100)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
>> at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:78)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
>> at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:119)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
>> at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:54)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
>> at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:35)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
>> at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:187)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
>> at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:105)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
>> at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:79)
>> at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:380)
>> at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:169)
>> at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
>> at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)
>> 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.apache.catalina.core.StandardHostValve