function validate_required(field,alerttxt)
{
with (field)
  {
  if (value==null||value=="")
    {
    alert(alerttxt);return false;
    }
  else
    {
    return true;
    }
  }
}

function validate_form(thisform)
{
with (thisform)
  {
  if (validate_required(nameTxt,"Please enter all required(*) fields!")==false)
  {nameTxt.focus();return false;}
  else if (validate_required(emailTxt,"Please enter all required(*) fields!")==false)
  {emailTxt.focus();return false;}
  else if (validate_required(subject_txt,"Please enter all required(*) fields!")==false)
  {subject_txt.focus();return false;}
 else if (validate_required(commentTxt,"Please enter all required(*) fields!")==false)
  {commentTxt.focus();return false;}
  }
}