function validate_contact_form( form )
{
  if( form.first_name.value.trim() == "" )
  {
    alert("First Name is required.");
    form.first_name.focus();
    return false;
  }// end if()
  
  if( form.email.value.trim() == "" )
  {
    alert("Email is required.");
    form.email.focus();
    return false;
  }// end if()
  
  if( ! /^[^\s@]+@[^\s@]+\.[^\s@]+$/i.test( form.email.value.trim() ) )
  {
    alert("Email is invalid.");
    form.email.focus();
    return false;
  }// end if()
  
  if( form.website.selectedIndex == 0 )
  {
    alert("Please select a Website.");
    form.website.focus();
    return false;
  }// end if()
  
  if( form.comments.value.trim() == "" )
  {
    alert("Please enter Your Message.");
    form.comments.focus();
    return false;
  }// end if()
  
  // Validation passed:
  return true;
}// end validate_contact_form( form )