SEVERE: Servlet.service() for servlet serv1 threw exception
java.lang.NoSuchFieldError: INSTANCE
at org.hibernate.type.BasicTypeRegistry.<init>(BasicTypeRegistry.java:94)
at org.hibernate.type.TypeResolver.<init>(TypeResolver.java:59)
at org.hibernate.cfg.Configuration.<init>(Configuration.java:250)
at org.hibernate.cfg.Configuration.<init>(Configuration.java:302)
at org.hib.HibernateSessionFactory.<clinit>(HibernateSessionFactory.java:24)
at org.hib.BaseHibernateDAO.getSession(BaseHibernateDAO.java:13)
at org.hib.Ex1DAO.insert(Ex1DAO.java:145)
at serv1.doPost(serv1.java:81)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
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.StandardWrapperValve.invoke(StandardWrapperValve.java:230)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:261)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:581)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)

You're mixing different versions of Hibernate jars. That will not work.