Hi Mike,
Please check the module documentation: https://www.metacpan.org/module/JSON#BACKEND-MODULE-DECISION Does this help? Do you have different backend modules in the different situations?
On both sites backend module is JSON::XS (i've updated problem description: http://sanchez.wasilkow.pl/json-problem.html#backend). Can this affect results i get? I think that using same backend should give same effect.
I will try to force using JSON::PP and see if this changes something. Patryk
