Tomcat Error: ...is quoted with " which must be escaped when used within the value

From Apache Tomcat 5.5.27 onwards, it seems that Tomcat is picky about double quoted expressions:

ERROR [http-80-Processor22] - Servlet.service() for servlet jsp threw exception
org.apache.jasper.JasperException: /forum/index.jsp(73,36) Attribute value request.getRequestURI()+"?"+request.getQueryString() is quoted with " which must be escaped when used within the value
at org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:40)
at org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:407)
at org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:198)
at org.apache.jasper.compiler.Parser.parseQuoted(Parser.java:307)
at org.apache.jasper.compiler.Parser.parseAttributeValue(Parser.java:250)
at org.apache.jasper.compiler.Parser.parseAttribute(Parser.java:211)
at org.apache.jasper.compiler.Parser.parseAttributes(Parser.java:149)
at org.apache.jasper.compiler.Parser.parseParam(Parser.java:875)
at org.apache.jasper.compiler.Parser.parseBody(Parser.java:1829)
at org.apache.jasper.compiler.Parser.parseOptionalBody(Parser.java:1081)
at org.apache.jasper.compiler.Parser.parseInclude(Parser.java:909)
at org.apache.jasper.compiler.Parser.parseStandardAction(Parser.java:1232)
at org.apache.jasper.compiler.Parser.parseElements(Parser.java:1588)
at org.apache.jasper.compiler.Parser.parse(Parser.java:132)
at org.apache.jasper.compiler.ParserController.doParse(ParserController.java:212)
at org.apache.jasper.compiler.ParserController.parse(ParserController.java:101)
at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:156)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:296)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:277)
at org.apache.jasper.compiler.Compiler.compile(Compiler.java:265)
at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:564)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:302)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:329)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
at com.cj.trim.trimFilter.doFilter(Unknown Source)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
at gr.knowledge.util.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:121)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:172)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:174)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:875)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
at java.lang.Thread.run(Unknown Source)

See the relevant https://issues.apache.org/bugzilla/show_bug.cgi?id=45015

It seems that, you can either edit your jsp code to be more compliant or get rid of the error by editing catalina.properties and putting this extra line:

org.apache.jasper.compiler.Parser.STRICT_QUOTE_ESCAPING=false

This actually tells Tomcat to be more relaxed about JSP compliance regarding double quoted expressions.

See also http://tomcat.apache.org/tomcat-5.5-doc/config/systemprops.html