Can't run a web application with gwtext

I am using the GWT and the GWTExt libraries with Eclipse for the first time. I have followed all the procedures but when I go run the web application the following error appears:

1) In the Problems tab, I have this message:

Description Resource Path Location Type The following classpath entry 'C:\Documents and Settings\CiuffreA\Desktop\GWTExt\gwtext-2.0.5\gwtext.jar' will not be available on the server's classpath GWTProject Unknown Google Web App Problem

2) In the Development Mode tab, the following 2 messages appears:

23:41:25.906 [ERROR] [mockupproject] Unable to load module entry point class com.example.myproject.client.MockUpProject 
Failed to load module 'mockupproject' from user agent 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US) AppleWebKit/532.5 (KHTML, like Gecko) Chrome/4.1.249.1042 Safari/532.5' at localhost:3853

If any开发者_JAVA百科one has a clue about where the problem may be, please give me a hint...

You can get the "x.jar will not be available on the server's classpath" if you are referencing the jar via Eclipse's "Java Build Path" outside of the war/WEB-INF/lib directory--and it looks like from the error that you are. Copy gwtext.jar to the project's war/WEB-INF/lib folder and tell Eclipse to find it there instead.

I'm not sure if your second problem is related (I don't think it is), but check your module's XML file and be sure everything is correct there (in particular make sure your changes for GWText are correct).

Edit: If you are using the GWT-Ext widget library, note that it is no longer under development and has been replaced with SmartGWT. It's possible that you are using a newer version of GWT and something has changed that is causing an exception in GWT-Ext's code (but you should see that exception listed if this is the case--is there a stack trace listed with the error?).