Even with the latest release, which is due out next week, sprites will not be supported.
However, that's a very interesting suggestion and I have created a PITS item for it -- http://www.telerik.com/support/pits.aspx#/public/aspnet-ajax/11253
-- which you can vote on. As soon as it gathers some voices, we'll consider it for implementation.
For your suggestion I have awarded you some Telerik points, which you can see updated in your account profile.
the Telerik team
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