Try the following:
var button = $('<button type="button"/>');
, , "button" IE ( , 7, 8). . . IE , , jQuery DOM API.
, FF Chrome .
edit β , ? jQuery 1.4.4 jQuery 1.5.x. , jQuery 1.6, , , OP: "type" , jQuery.
, , , ".setAttribute()" . :
var b = $('<button/>');
b[0].setAttribute('type', 'button');
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