Looks like there is a newer version 3.0.19 (we are on 3.0.16). It seems they have been active [1]. Worth an upgrade?
[1] https://code.google.com/p/gwtwiki/source/list
It seems there is a fix for templates that take a long time to resolve (possibly infinitely?) It seems we could set a parser recursion limit (Configuration.PARSER_RECURSION_LIMIT)
https://code.google.com/p/gwtwiki/source/detail?r=9055#