Build 1104: NoClassDefFoundError com/intellij/uiDesigner/core/GridLayoutManager

I have designed a small test project to see the GUI capabilities of new Idea
4.
After I designing a form and binding it to fields and a class I got the
NoClassDefFoundError exception!
That is because I used Grid layout.

ava.lang.NoClassDefFoundError:
com/intellij/uiDesigner/core/GridLayoutManager

From where can I get this library?

(This exception comes only when compiling. Not at designing. Is it because
they have scrammbled the classes in the libraries?)

Lasantha Kularatne.