Why add port could not get Cookie?

I am added a cookie key-value paire in firefox using firebug.

myid:12345

And get cookie from server like this:

var ccnid = CookieUtil.GetValue("myid");
Response.Write("myid:"+myid);
Response.End();

My website url like this:http://ift.tt/1PntLDZ.

When set cookie domain like this:http://192.168.1.222. i browser the url:http://ift.tt/1PntLDZ, the response is:myid:123456.

When set cookie domain like this:http://ift.tt/1PntLDZ. i browser the url:http://ift.tt/1PntLDZ, the response is:myid:.

Why could this happen?The domain:http://ift.tt/1PntLDZ could not access http://ift.tt/1PntLDZ?