JSON is terribly simple. Make a PHP array, output the result of
json_encode of your array and
eval() it in JScript.
If you want to go one step further, you could steal some functions from a JavaScript framework like PrototypeJS or jQuery to check the received JSON code for any potentially malicious code, such as function calls. However in a case of a simple Plus! script, you probably won't really need such extra security measures.
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