Spritely jQuery plugin and the pan() method

OK, I'm trying to include some animating backgrounds using Spritely as a test on my website but I'm having some problems.

For some reason, I cannot get the background to pan correctly.

I use this jQuery in my document ready event handler:

$('#bg_1').pan({fps: 30, speed: 2, dir: 'right'});

And then firebug gives me the following error:

$("#bg_1").pan is not a function

Now, this should work considering my JS spritely file appears to be linked properly.

If you would like to view the problem live here is the site URL: http://www.ma开发者_StackOverflow中文版rioplanet.com

Any ideas as to why pan() isn't recognized as a function?

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OK everyone, for those that have this problem in the future here is what I have found:

For some reason, the compressed version of the Spritely jQuery plugin had a problem, as when I called the pan() method, it wasn't recognized as a function.

For some reason, downloading the full, uncompressed version instead of the compressed made it work beautifully!

Check out the effect here, it's pretty sick, and really easy to do! :) http://www.marioplanet.com