You like the functionality, but do not grock Java for your project?
Do not despair. JWt exists in a native variant or through bindings in other languages:
Leveraging the JVM's support for other languages, such as Clojure, a LISP variant, Ralph Moritz is experimenting with using JWt from within Clojure, documenting his experience in his blog and eventually developing a small support library.
Albert Cervera i Areny is experimenting to use JWt from Jython, another language running on the JVM. He documents how to create and run the "Hello World!" program in Jython in this blog post.
If you prefer C++, you should consider using Wt, the C++ version, which is developed and maintained together with the Java version, and from which the Java version is derived. It comes with application server included.
Richard Dale is maintaining WtRuby, Ruby bindings to Wt, using the same framework used for generating Ruby bindings to Qt and KDE.