Yesterday (2011-07-31) we have finished the project (development and support) of the modernization of Cool:GEN code base to java for the Chicago Mercantile Exchange.
It wasn't the first such project but definitely most interesting. We have migrated and tested about 300 MB of source code. In the process of translation we have identified many bugs that were present in the original code. Thanks to languages-xom that task turned to be pure xslt.
We hope that CME's developers are pleased with results.
If you by chance is looking for Cool:GEN conversion to java, C#, or even COBOL (don't understand why people still asking for COBOL) then you can start at bphx site.