corner image could not be found.

I tried making a call to SC.showPrompt and this is the error I got?

12:37:42.824 [ERROR] [apt] 12:37:42.824:RDQ6:WARN:Scrollbar:isc_ESDAbstractPanel_1_0_body_vscroll:setImage: image ‘corner’ couldn’t be found
com.smartgwt.client.core.JsObject$SGWT_WARN: 12:37:42.824:RDQ6:WARN:Scrollbar:isc_ESDAbstractPanel_1_0_body_vscroll:setImage: image ‘corner’ couldn’t be found
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:105)
at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:157)
at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:281)
at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:531)
at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:352)
at java.lang.Thread.run(Thread.java:619)

Without more information we can’t tell what’s causing this - however this warning shouldn’t actually impact your application in most cases.

If your saying the warn dialog is failing to show, most likely something else is going on here as well.
Any chance you can show us a test case demonstrating the problem?

Thanks

showing the problem:

http://youtu.be/A6IxT7rSeME