[jQuery] BlockUI: What's wrong with this code?

[Chris Jordan]

Can anyone tell me what's wrong with the following code:

            $(function(){
                $(".thumb").bind("mouseover", function(){
                    $(this).blockUI({
                        message: $(this).attr("alt")
                    })
                }).bind("mouseout",function(){
                        $(this).unblockUI();
                });
            });

the "thumb" class is applied to a bunch of images on my page. when I
mouseover the image I want a layer put up over just that image along with a
message (the alternate text). The error I get is: $(this).blockUI() is not a
function. Likewise I get the same on the mouseout only with the appropriate
function name listed in the error.

Can anyone tell me what I'm doing wrong?

Thanks!
Chris

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