Exception when Soapui 4.0 Start

Hi, All,

I start Soapui 4.0, then system show the following error message:
Can anyone help me?
Thanks in advance!

2011-06-28 14:15:30,740 INFO [DefaultSoapUICore] Adding actions from [D:\soapUI-Pro-4.0.0\bin\actions\demo-actions.xml]
2011-06-28 14:15:32,285 ERROR [cx]
java.lang.SecurityException: class "com.jniwrapper.win32.bj"'s signer information does not match signer information of other classes in the same package
at java.lang.ClassLoader.checkCerts(Unknown Source)
at java.lang.ClassLoader.preDefineClass(Unknown Source)
at java.lang.ClassLoader.defineClassCond(Unknown Source)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$000(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at com.jniwrapper.win32.automation.types.BStr.<init>(SourceFile:108)
at com.jniwrapper.win32.automation.types.BStr.<init>(SourceFile:118)
at com.jniwrapper.win32.com.types.CLSID.<init>(SourceFile:51)
at com.jniwrapper.win32.com.types.CLSID.create(SourceFile:89)
at com.jniwrapper.win32.ie.au.<init>(Unknown Source)
at com.jniwrapper.win32.ie.cn.<init>(Unknown Source)
at com.jniwrapper.win32.ie.cx.<init>(Unknown Source)
at com.jniwrapper.win32.ie.Browser.a(Unknown Source)
at com.jniwrapper.win32.ie.Browser.<init>(Unknown Source)
at com.jniwrapper.win32.ie.Browser.<init>(Unknown Source)
at com.teamdev.jxbrowser.ie.IEBrowser.<init>(Unknown Source)
at com.teamdev.jxbrowser.ie.IEBrowserFactory.create(Unknown Source)
at com.teamdev.jxbrowser.BrowserFactory.createBrowser(Unknown Source)
at com.teamdev.jxbrowser.BrowserFactory.createBrowser(Unknown Source)
at com.eviware.soapui.support.components.NativeBrowserComponent.initBrowser(NativeBrowserComponent.java:185)
at com.eviware.soapui.support.components.NativeBrowserComponent.getComponent(NativeBrowserComponent.java:103)
at com.eviware.soapui.ui.URLDesktopPanel.<init>(URLDesktopPanel.java:38)
at com.eviware.soapui.SoapUI.showPushPage(SoapUI.java:1332)
at com.eviware.soapui.SoapUI$3.run(SoapUI.java:803)
at java.awt.event.InvocationEvent.dispatch(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$000(Unknown Source)
at java.awt.EventQueue$1.run(Unknown Source)
at java.awt.EventQueue$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(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)

Best Regards,
Roy