IBM developerWorks has recently published an article by Sergey Odobetskiy about integrating ActiveWidgets grid with GWT -
http://www-128.ibm.com/developerworks/web/library/j-gwtcontrols/index.html
"The Google Web Toolkit (GWT) provides libraries and tools that let you develop Ajax applications in the Java™ programming language. Unfortunately, GWT's standard gallery of UI controls (widgets) doesn't provide the advanced features that modern enterprise applications require. This article shows a technique that addresses this deficiency. Find out how to give GWT controls advanced functionality with relatively simple coding by integrating a popular JavaScript grid component with a GWT application."
The article includes code examples and sample GWT application.
Thanks for the link, Alex. My company is considering GWT, and integration of the AW grid is critical.