If the striping is only for styling, you can sidestep this whole problem just using CSS.
tr:nth-child(2n) {
background: gray;
}
tr:nth-child(2n+1) {
background: lightgray;
}
If you really need some function to run after sorting takes place, a quick glance at the documentation suggests that you might do it like this:
$("table").bind("sortEnd", function() {
// ...
});