Database population with JQuery strings

How can I avoid getting new strings in the database each time an ajax message is handled in my web site? For instance, I’m using the plugin login-with-ajax, everytime a user logs in, a new string is created in the database like this:
jQuery37107345757965089613_1752797648078({“result”:true,”message”:”Login Successful, redirecting…”,”action”:”login”})

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