function textboxchanged()
        {  
            if(document.getElementById('comments').value != '')
            {
                document.getElementById('Button1').disabled = false;
            }
            else
                document.getElementById('Button1').disabled = true;
        }
        
        function cleartext()
        {
            if(document.getElementById('comments').value == 'Thank you for your comments.')
            {
                document.getElementById('comments').value = '';
            }
        }
        
        function validate() 
        {
            var addr = document.getElementById('email').value;

            if (addr == '') return true;
            
            var invalidChars = '\/\'\\ ";:?!()[]\{\}^|';
            
            for (i=0; i<invalidChars.length; i++) 
            {
               if (addr.indexOf(invalidChars.charAt(i),0) > -1) 
               {
                    ShowBadEmailAddressMessage();
                    return false;
               }
            }
            
            for (i=0; i<addr.length; i++) 
            {
               if (addr.charCodeAt(i)>127) 
               {
                  ShowBadEmailAddressMessage();
                  return false;
               }
            }

            var atPos = addr.indexOf('@',0);
            if (atPos == -1) {
               ShowBadEmailAddressMessage();
               return false;
            }
            if (atPos == 0) {
               ShowBadEmailAddressMessage();
               return false;
            }
            if (addr.indexOf('@', atPos + 1) > - 1) {
               ShowBadEmailAddressMessage();
               return false;
            }
            if (addr.indexOf('.', atPos) == -1) {
               ShowBadEmailAddressMessage();
               return false;
            }
            if (addr.indexOf('@.',0) != -1) {
               ShowBadEmailAddressMessage();
               return false;
            }
            if (addr.indexOf('.@',0) != -1){
               ShowBadEmailAddressMessage();
               return false;
            }
            if (addr.indexOf('..',0) != -1) {
               ShowBadEmailAddressMessage();
               return false;
            }
            var suffix = addr.substring(addr.lastIndexOf('.')+1);
            if (suffix.length != 2 && suffix != 'com' && suffix != 'net' && suffix != 'org' && suffix != 'edu' && suffix != 'int' && suffix != 'mil' && suffix != 'gov' & suffix != 'arpa' && suffix != 'biz' && suffix != 'aero' && suffix != 'name' && suffix != 'coop' && suffix != 'info' && suffix != 'pro' && suffix != 'museum') {
               ShowBadEmailAddressMessage();
               return false;
            }
            return true;
        }
        
        function ShowBadEmailAddressMessage()
        {
            alert('Please enter a valid email address');
        }