Windows 7 64 bit, Skype 5.3.0, href="callto://" it keep open infinite FF process. Can't be stop in any way except KILL all FF, Skype and related process. '''The problem is even WORST!''' If you have FF as main browser and you try to open a callto:// (skype) link from another browser (ex: chrome) ... skype will start, FF will start and start to loop forever it keep open new blank pages with callto://callto://callto://callto://etc.. etc.. (infinite time) even if you try to close skype or if you try to close FF or if you try to close chrome nothing change! It's a SUPER-IMBA flooding memory exploit!