hex_chars=Array('0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f');
hash='';
hash_length=20;
for(h=0;h<hash_length;h++) {
hash=hash+hex_chars[Math.floor(16*Math.random())];
}
document.getElementById('vrCaptchaHash').value=hash;
captcha_image_url='https://captcha.vresp.com/produce/'+hash;
document.getElementById('vrCaptchaImage').src=captcha_image_url;