anchor.diff:  
           <c:when test="${not empty requestScope['exception']}">
               <p>
  -                <c:out value="${requestScope['exception'].message}"/>
  +                <c:out value="${fn:escapeXml(requestScope['exception'].message)}"/>
               </p>
   
               <security:authorize access="hasRole('GROUP_ADMIN')">
  
positive.code:         <c:when test="${not empty requestScope['javax.servlet.error.exception']}">
  
              <p>
                  <c:out value="${requestScope['javax.servlet.error.exception'].message}"/>
              </p>
  
              <security:authorize access="hasRole('GROUP_ADMIN')">
  
negative.code:             <li>Do you need to log in?</li>
              <c:choose>
                  <c:when test="${not empty param.exception}">
                      <li><a href="mailto:pavlab-support@msl.ubc.ca?subject=${fn:escapeXml(param.exception.message)}">Email us</a> about
                          the problem.
                      </li>
                  </c:when>
                  <c:when test="${not empty requestScope['javax.servlet.error.exception']}">
                      <li>
                          <a href="mailto:pavlab-support@msl.ubc.ca?subject=${fn:escapeXml(requestScope['javax.servlet.error.exception'])}">Email
                              us</a> about the problem.
                      </li>
                  </c:when>
                  <c:when test="${not empty requestScope['exception']}">
                      <li><a href="mailto:pavlab-support@msl.ubc.ca?subject=${fn:escapeXml(requestScope['exception'])}">Email us</a>
                          about the problem.
                      </li>
                  </c:when>
  