I updated to beta2 and i noticed that po files are no more supported, only json are... Not a good suprise but anyway...
As I already have a complex buildchain, i don't use your "bin/compilers", I use the last po2json lib to convert my po files to json.
Eval function is evil for many reasons and should not be used in that case because you just want to parse the json to an object and JSON.parse() is here for that.
your block near line 82 would just be :
var json_locale_data = JSON.parse(fs.readFileSync(json_file_path(l)).toString());
Removing use of eval. Fixes Issue #19
A more robust fix needs to be coordinated in mozilla/browserid
as well as Issue #15.
Fixed in commit 648dec4e203fbe93ea99cb7718b5106be9a30c82