function getBIDFromQstring() { 
var url = document.location+''; // Insures string 
q=url.split('?'); 
if (q[1]) { 
var pairs = q[1].split('&'); 
for (i=0;i<pairs.length;i++) { 
var keyval = pairs[i].split('='); 
if (keyval[0] == 'BID') { var v = keyval[1]; break; } 
} 
} 
if (v) { return v; } 
}
var BID = getBIDFromQstring(); 
if (BID) { document.BIDform.BID.value=BID; }