The Exim Webapp version is shown in the <display-name> element in
the web.xml file.
You will need a JDK of Java 1.4 (i.e., the Development kit, not just a Runtime) and Ant 1.6.0 or newer to build Exim Webapp from source. (I use nested build files, so Ant 1.5.x or earlier won't do).
The top level directory has the Exim Webapp version in its name.
After you unzip it, just run ant -projecthelp inside of the
top-level directory.
If anybody would like to help with development of Exim Webapp, definitely email me at blaine.simpson@admc.com.