axis : java.lang.NoSuchMethodError

Hi friends,
Iam getting the following error when deploying my app in jboss error.Iam new to axis .can you please help..
2006-01-31 10:04:04,685 WARN [org.jboss.jbossweb] WARNING: Exception for /proweb/QasController
java.lang.NoSuchMethodError: org.apache.axis.description.ElementDesc.setNillable(Z)V
at com.qas.proweb.soap.QASearch.<clinit>(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:141)
at com.qas.proweb.soap.QASoapBindingStub.class$(Unknown Source)
at com.qas.proweb.soap.QASoapBindingStub._initOperationDesc1(Unknown Source)
at com.qas.proweb.soap.QASoapBindingStub.<clinit>(Unknown Source)
at com.qas.proweb.soap.ProWebLocator.getQAPortType(Unknown Source)
at com.qas.proweb.QuickAddress.<init>(Unknown Source)
at com.qas.proweb.servlet.FlatPromptEntry.execute(Unknown Source)
at com.qas.proweb.servlet.Controller.processRequest(Unknown Source)
at com.qas.proweb.servlet.Controller.doPost(Unknown Source)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:360)
at org.mortbay.jetty.servlet.WebApplicationHandler.dispatch(WebApplicationHandler.java:294)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:558)
at org.mortbay.http.HttpContext.handle(HttpContext.java:1714)
at org.mortbay.jetty.servlet.WebApplicationContext.handle(WebApplicationContext.java:507)
at org.mortbay.http.HttpContext.handle(HttpContext.java:1664)
at org.mortbay.http.HttpServer.service(HttpServer.java:863)
at org.jboss.jetty.Jetty.service(Jetty.java:460)
at org.mortbay.http.HttpConnection.service(HttpConnection.java:775)
at org.mortbay.http.HttpConnection.handleNext(HttpConnection.java:939)
at org.mortbay.http.HttpConnection.handle(HttpConnection.java:792)
at org.mortbay.http.SocketListener.handleConnection(SocketListener.java:201)
at org.mortbay.util.ThreadedServer.handle(ThreadedServer.java:289)
at org.mortbay.util.ThreadPool$PoolThread.run(ThreadPool.java:455)

====================

This sounds like a mismatch of Axis versions, or possibly a corrupted Axis jar file. Check that all related jar files are OK, and that all jars go with the same version of Axis. Try to recompile everything related to the WS, and that it actually compiles against the jar files used during runtime.

=============================

Well, you seem to have more than version of the axis.jar file. So check all of them, and make sure they are identical. In particular, make sure that the one you develop against is the same version as the one you run against.