Sometimes you find JSON web services that doesn’t respect the format, just because javascript and some parsers also work that way. But you want to use it with a parser that only allows strict implementations.
So here you have a little piece of code that saved my butt (in Java). It uses String class replaceAll method.
malformedJson.replaceAll("(\s)*([a-zA-Z0-9_]+?):", "\"$2\":");
I’m not the most knowledgeable guy with regular expressions but that one is simple enough.