FreeMarker template error!


Expression fbLangCode is undefined on line 7, column 67 in front/decorators/front-sns-decorator.ftl.
The problematic instruction:
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==> ${fbLangCode} [on line 7, column 65 in front/decorators/front-sns-decorator.ftl]
 in include "/front/decorators/front-sns-decorator.ftl" [on line 33, column 1 in front/decorators/front-default-decorator.ftl]
----------

Java backtrace for programmers:
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freemarker.core.InvalidReferenceException: Expression fbLangCode is undefined on line 7, column 67 in front/decorators/front-sns-decorator.ftl.
	at freemarker.core.TemplateObject.assertNonNull(TemplateObject.java:125)
	at freemarker.core.Expression.getStringValue(Expression.java:118)
	at freemarker.core.Expression.getStringValue(Expression.java:93)
	at freemarker.core.DollarVariable.accept(DollarVariable.java:76)
	at freemarker.core.Environment.visit(Environment.java:221)
	at freemarker.core.MixedContent.accept(MixedContent.java:92)
	at freemarker.core.Environment.visit(Environment.java:221)
	at freemarker.core.Environment.include(Environment.java:1508)
	at freemarker.core.Include.accept(Include.java:169)
	at freemarker.core.Environment.visit(Environment.java:221)
	at freemarker.core.MixedContent.accept(MixedContent.java:92)
	at freemarker.core.Environment.visit(Environment.java:221)
	at freemarker.core.Environment.process(Environment.java:199)
	at freemarker.template.Template.process(Template.java:237)
	at freemarker.ext.servlet.FreemarkerServlet.process(FreemarkerServlet.java:452)
	at freemarker.ext.servlet.FreemarkerServlet.doGet(FreemarkerServlet.java:391)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:684)
	at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:593)
	at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:530)
	at com.opensymphony.sitemesh.compatability.OldDecorator2NewDecorator.render(OldDecorator2NewDecorator.java:46)
	at com.opensymphony.sitemesh.webapp.decorator.BaseWebAppDecorator.render(BaseWebAppDecorator.java:33)
	at com.opensymphony.sitemesh.webapp.SiteMeshFilter.doFilter(SiteMeshFilter.java:84)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.struts2.dispatcher.ActionContextCleanUp.doFilter(ActionContextCleanUp.java:102)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
	at com.googlecode.psiprobe.Tomcat70AgentValve.invoke(Tomcat70AgentValve.java:38)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
	at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
	at org.apache.coyote.ajp.AjpProcessor.process(AjpProcessor.java:200)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
	at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:302)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
	at java.lang.Thread.run(Thread.java:722)
[Mnet]??No.1 ????????????????Mnet
ERROR ????????????

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