From Facebook Developer Wiki

Why does this button always come with an "or" in front of it? Not only does it do that no matter what the language of the user is, it is also not possible to turn it off or to translate it.

I'd imagine the "or" is by design, since the cancel should be one of >1 options. I filed a bug about getting the string translated: http://bugs.developers.facebook.com/show_bug.cgi?id=4069 -- Pete (563683308 13:43, 7 January 2009 (PST))