function validateForm(){
	 element = document.getElementById('theform');
   if ( ! validate_email ( element.email.value, element.email ) ) {
      return false;
   }
   document.getElementById('continueButton').disabled=true;
   return true;
}
function validate_email ( email_val, email_element ) {
   if ( ! check_for_text ( email_val ) ) {
      error_message ( email_element,
                      "Please enter your email address." );
      return false;
   }
                                   
   if ( ! check_email ( email_val ) ) {
      error_message ( email_element,
                      "Invalid email address." );
      return false;
   }

   return true;
}
function check_email ( email_value ) {
   var email_ats    = 0;
   var email_dots   = 0;   
   var at_position  = 0;
   var dot_position = 0;
   var email_spaces = 0;                       
   var i;
                         
   if ( email_value.length < 6 ) {
      return false;
   }  
                         
   for ( i = 0; i < email_value.length; i++ ) {
      if ( email_value.charAt (i) == "@" ) {
         email_ats++;                                         
         at_position = i;
      }                 
      if ( email_value.charAt (i) == "." ) {
         email_dots++;  
         dot_position = i;  // Will be set to last occurrence
      }            
      if ( email_value.charAt (i) == " " ) {
         email_spaces++; 
      }                    
   }
      
   if ( ( email_ats == 0 ) || ( email_ats > 1 ) ) {
      return false;
   }                  
      
   if ( email_dots == 0 ) {
      return false;
   }                  
      
   // Email must have characters after the @ sign:
   if ( ( email_value.charAt ( at_position + 1 ) == "" ) ||   
        ( email_value.charAt ( at_position + 1 ) == " " ) ) {
      return false;     
   }
                           
   // Email must have characters after the dot:              
   if ( ( email_value.charAt ( dot_position + 1 ) == "" ) ||
        ( email_value.charAt ( dot_position + 1 ) == " " ) ) {
      return false;
   }                       
       
   // Email must have characters before the @ sign:
   if ( ( email_value.charAt ( at_position - 1 ) == "" ) ||
        ( email_value.charAt ( at_position - 1 ) == " " ) ) {
      return false;   
   }
      
   // Email must have characters before the dot:
   if ( ( email_value.charAt ( dot_position - 1 ) == "" ) ||
        ( email_value.charAt ( dot_position - 1 ) == " " ) ) {
      return false;
   }
           
   // Email must have dot after @ sign:
   if ( dot_position < at_position ) {
      return false;     
   }
      
   if ( email_spaces > 0 ) {
      return false; 
   }                       
       
   return true;
}
function check_for_text ( elem_value ) {              
   var text_entry = 0;              
   var i;
                      
   for ( i = 0; i < elem_value.length; i++ ) {
      if ( elem_value.charAt (i) != " " ) {
         text_entry = 1;                           
      }
   }

   if ( text_entry == 0 ) {
      return false;
   }
   return true;
}
function error_message ( elem, text ) {
   window.alert ( text );
   elem.select ();
   elem.focus ();
}