JQuery :: IE/Opera Ignoring Load() Function?

I'm using the following chunk of code to find images located in a specific span and then I'm setting the span width to equal the width of the image that's inside of it. This is for adding captions to images through an editor that our writers use. By forcing the span to equal the same width of the image, the writers can just enter whatever captions they want and don't have to worry about manually adding <br /> tags to format the captions correctly.

$('.overview-content .caption img')
// once the image has loaded, execute this code
.load(function() {
// Loop through and find all images in the overview section

[Code].....

For some reason... IE and Opera completely ignore this function. Firefox, Safari and Chrome all add the appropriate inline style to the span.