private bool ValidateChangePassword(string currentPassword, string newPassword, string confirmPassword)
        {
            if (String.IsNullOrEmpty(currentPassword))
            {
                ModelState.AddModelError("currentPassword", "You must specify a current password.");
            }
            if (newPassword == null || newPassword.Length < MembershipService.MinPasswordLength)
            {
                ModelState.AddModelError("newPassword",
                    String.Format(CultureInfo.CurrentCulture,
                         "You must specify a new password of {0} or more characters.",
                         MembershipService.MinPasswordLength));
            }

            if (!String.Equals(newPassword, confirmPassword, StringComparison.Ordinal))
            {
                ModelState.AddModelError("_FORM", "The new password and confirmation password do not match.");
            }

            return ModelState.IsValid;
        }