I think the problem may be a version of the Twitter widget.js file that is being supplied. I made a basic html page with only this as the code in the body:
Tweet
The TypeError in the subject shows up in Chrome under the dev tools. In IE, " {exception} Object doesn’t support property or method ‘init’ " show up in the dev tools. This was code mostly taken directly from https://dev.twitter.com/docs/tfw/events and still gives the same error. If anyone can confirm my hypothesis this would be nice.
Additional info from IE:
Anonymous function [Line: 44, Col: 1047], widgets.js
T.prototype.complete [Line: 1, Col: 3091], widgets.js
t [Line: 1, Col: 5177], widgets.js
T.prototype.complete [Line: 1, Col: 3091], widgets.js
N.prototype.complete [Line: 1, Col: 3997], widgets.js
C.prototype.complete [Line: 1, Col: 4609], widgets.js
C.prototype.exp [Line: 1, Col: 4849], widgets.js
Anonymous function [Line: 1, Col: 4546], widgets.js
T.prototype.then [Line: 1, Col: 2752], widgets.js
C.prototype.loaded [Line: 1, Col: 4527], widgets.js
n.onload [Line: 1, Col: 3759], widgets.js
The same type of information shows up in Chrome.
I have also asked this question on stackoverflow: http://stackoverflow.com/questions/24683865/twitter-uncaught-typeerror-undefined-is-not-a-function/24698352#24698352