After few days 5 or 6 the application is hanging in the initial page and the tomcat manager also not opening, When we restart the server and if there any java process if we kill and restart the n the application is running, and same after few days, the message that appears in the logs if the following
please give me the reaseon or solution to fix this


StandardWrapper[/bts:org.apache.catalina.INVOKER.images]: Marking servlet org.apache.catalina.INVOKER.images as unavailable
2005-09-04 11:58:42 invoker: Cannot allocate servlet instance for path /bts/servlet/images/blank.gif
javax.servlet.ServletException: Wrapper cannot find servlet class images or a class it depends on
    at org.apache.catalina.core.StandardWrapper.loadServl et(StandardWrapper.java:891)
    at org.apache.catalina.core.StandardWrapper.allocate( StandardWrapper.java:668)
    at org.apache.catalina.servlets.InvokerServlet.serveR equest(InvokerServlet.java:416)
    at org.apache.catalina.servlets.InvokerServlet.doGet( InvokerServlet.java:180)
at javax.servlet.http.HttpServlet.service(HttpServlet .java:740)
    at javax.servlet.http.HttpServlet.service(HttpServlet .java:853)
    at javax..apache.catalina.core.ApplicationFilterChain .internalDoFilter(ApplicationFilterChain.java:247)
    at org.apache.catalina.core.ApplicationFilterChain.do Filter(ApplicationFilterChain.java:193)


Rajeshn