GWT DateField - 'ExceptionInInitializerError'

Question

Hello,

I am new to GWT. I am trying to develop a GWT application. In my project I am using a 'DateField' as follows,
DateField dob = new DateField("Birthday", "d/m/y");
When I am trying to run in hosted mode, I am getting the error

java.lang.ExceptionInInitializerError: null

I am using Google plugin for Eclipse 3.5 (Version - 1.1.1.v200909221731),
Google Web Toolkit SDK 1.7.1( Version -1.7.1.v200909221731),
ext-2.0.2

Please guide me on this. Any pointers are welcome.

Thanks,

SD