rm_callback is being forgotten on safari browsers.

[beberry]

I have noticed that the rm_callback function is being forgotten on safari browsers.For testing purpouses I added an alert() method to the rm_callback, to see when it's being launched. If you go to a test page - http://bit.ly/12xxw36 you can se that after pressing on the red button located on the right side bottom, the callback is being launched on mozilla & chrome, but not on safari.

I assume that this is a bug, if not at least I'll find the reason of this behaviour, as for now I am not able to resize the iframe on safari devices..