Not works correctly in IE8+

[yauhen]

Here is small sample:
http://jsbin.com/ayepiLe/1/

just open 4 tabs in any ie. Then move on 3rd for example. press login button. Depending on some random not all tabs have alert generated but 4th tab never fires anyway. have tried to use timeouts, replace alert on other methods (to not block) etc. without any success.