Yesterday I discovered a problem on one of my sites: escape function was encoding the same string Salò in two different ways:
This was happening on Firefox 18.104.22.168. In Opera 9.20 was encoded ok every time.
So, in Firefox was a russian roulette :). Sometimes was encoding the string like I wanted to, sometimes not. As a solution I use encodeURIComponent(), but the behavior of escape() seems strange to me.