applet跟servlet之间通讯异常,请帮忙看看!

java.io.IOException: Server returned HTTP response code: 500 for URL: http://10.203.116.191:19001/admin/menu/menuservlet
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at com.huaheng.psp.admin.menu.agent.MenuAgentImpl.sendRequest(MenuAgentImpl.java:103)
at com.huaheng.psp.admin.menu.agent.MenuAgentImpl.sortMenu(MenuAgentImpl.java:137)
at com.huaheng.psp.admin.menu.applet.JTreeTransferHandler.syncToServer(JTreeTransferHandler.java:229)
at com.huaheng.psp.admin.menu.applet.JTreeTransferHandler.importData(JTreeTransferHandler.java:177)
at javax.swing.TransferHandler$DropHandler.drop(Unknown Source)
at java.awt.dnd.DropTarget.drop(Unknown Source)
at javax.swing.TransferHandler$SwingDropTarget.drop(Unknown Source)
at sun.awt.dnd.SunDropTargetContextPeer.processDropMessage(Unknown Source)
at sun.awt.dnd.SunDropTargetContextPeer.access$800(Unknown Source)
at sun.awt.dnd.SunDropTargetContextPeer$EventDispatcher.dispatchDropEvent(Unknown Source)
at sun.awt.dnd.SunDropTargetContextPeer$EventDispatcher.dispatchEvent(Unknown Source)
at sun.awt.dnd.SunDropTargetEvent.dispatch(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processDropTargetEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
请高手指点！