If you upgrade from the 2.x to the 3.x version of the Google Analytics module, and you use custom Javascript, you will have to manually upgrade it.

Google's documentation shows the overall migration steps, and how the ._gaq object, used in the asynchronous code, works.

Here's an example of how to change the "after" code if you want to track a second account:

// Traditional (ga.js) Snippet, 2.x
var secondTracker = _gat._getTracker("UA-XXXXX-X");
secondTracker._trackPageview();

// Async Snippet, 3.x
_gaq.push(['b._setAccount', 'UA-XXXXX-X']);
_gaq.push(['b._trackPageview']);

Here's an example of the new event tracking code, which you would add either in page markup or via hook_form_alter by setting the onclick attribute of a link or button:

<a href="#" onClick="_gaq.push(['_trackEvent', 'Videos', 'Play', 'Baby\'s First Birthday']);">Play</a>

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