Commented Issue: Maskedit. Cant't use delete and backspace key [27069]

I've read all post here about this issue, but, none of them helped me.
I put this script:

try {
p = Sys.Extended.UI.MaskedEditBehavior.prototype;
} catch (e) {
p = null;
}
if (String.prototype.replaceAll == null) {
String.prototype.replaceAll = function(s, r) {
var x = "", i = this.indexOf(s, 0), k = 0;
while (i >= 0) {
x += this.substring(k, i) + r;
k = i + s.length;
i = this.indexOf(s, k);
}
return x + this.substring(k, this.length);
}
}
function funcbody(f) {
var s = f.toString();
return s.substring(s.indexOf('{'));
}
if (p != null) {
p._ExecuteNav = new Function("g", "h", 'var c=-1,e=" ",a="",b=false,d=true,p="keypress",s="keydown";' + funcbody(p._ExecuteNav).replaceAll('g.type==p', '(g.type==p||g.type==s)'));
}

like that other post said, but i'm getting this error message on Chrome: "evt is not defined".

So, how can i solve this? Won't the AJAX Contol Toolkit Team solve this problem?

Thank's
Comments: Someone posted a fix here... Can you please apply it to your code base? Thanks! http://code.google.com/p/chromium/issues/detail?id=3341#c15