$.noConflict()
This helps to make sure that jQuery doesn't conflict with the $ object of other libraries.
By using this function, you will only be able to access jQuery using the 'jQuery' variable. For example, where you used to do $("div p"), you now must do jQuery("div p").
NOTE: This function must be called
after including the jQuery javascript file, but before including any other conflicting library, and also before actually that other conflicting library gets used, in case jQuery is included last.
Сначала подключаем jQuery, потом вызов noConflict, потом prototype
UPD Ступил,
Octane все правильно написал