jQuery .animate() a single CSS attribute that has multiple values

[oKRamxII]

I'm trying to animating the background-position of an element using jQuery's .animate() method. The background-position attribute is set by defining both the x and y values, like so:\[code\]background-position: 100px 100px;\[/code\]Webkit now supports a \[code\]background-position-x\[/code\] and \[code\]background-position-y\[/code\], but it is not yet supported in Firefox. If I animate only one value