question on HTML_Quickform error message & smarty

I have a login form using HTML_Quickform and a smarty template. I seem to be having trouble getting the error message to show if the login fails. I have a custom rule that seems to be working according to the smarty debugger. I have error values set, but I can't seem to get them to show back in the form at all. Below is relevant code from both the php file, the .tpl, and the smarty debugger on a form submit Thanks for any help. Rick login.php (class extending HTML_Quickform): $this->addElement( 'header', 'login_header', 'Login' );

                             $fields[] = &HTML_QuickForm::createElement( 'text', 'username', 'Username', array('size' => 15, 'maxlength' => 25 ) );
               $fields[] = &HTML_QuickForm::createElement( 'password', 'password', 'Password', array('size' => 15, 'maxlength' => 25  ));
                             $this->addGroup($fields, 'fields', '<br />');
                             $this->addElement( 'submit', 'login_button', 'Login' );
                             $this->registerRule('login_user', 'callback', 'login_user', 'login');
                             $this->addGroupRule('fields', 'Invalid Username/Password!', 'login_user');
                             // set the renderer options
               $renderer = &new HTML_QuickForm_Renderer_ArraySmarty( $smarty );
                             $renderer->setErrorTemplate( '{$html} {if $error}
                                               <span class="error">{$error}</span>
                                               {/if}' );
                             if( $this->validate() ) {
                                     // marked that they are logged in
                   $smarty->assign( 'login', true );
                   $smarty->assign( 'Session', $_SESSION );
                                 }// end if form validated
               else {
                   $smarty->assign( 'login', false );
                   $this->accept( $renderer );
                   $smarty->assign( 'form_data', $renderer->toArray() );
               }// end if form did not validate

template user: login_form.tpl <form {$form_data.attributes}>

           <table cellpadding="0" cellspacing="0" border="0">                  <tr>
                   <td><img src="{$Base_Path}images/left_arc.gif" class="no_space"/></td>
                   <td align="center" bgcolor="#006600" width="100%"class="login_form_header">{$form_data.header.login_header}</td>
                   <td><img src="{$Base_Path}images/right_arc.gif" class="no_space" /></td>
               </tr>
           </table>
       <div class="login_form" align="center">
           <span class="login_form_label">{$form_data.fields.username.label}</span>
           {$form_data.fields.username.html}
           <br />
           <span class="login_form_label">{$form_data.fields.password.label}</span>
           {$form_data.fields.password.html}
           <div align="center">
               <span class="login_form_label">{$form_data.login_button.label}</span>
               {$form_data.login_button.html}
               <br /><br />
               <hr />
               <br />
               <div>
                   <a href="{$Base_Path}login.php?action=user_account">New User</a>
                   <br />
                   <a href="{$Base_Path}login.php?action=forgot_password">Forgot Login</a>
               </div>
           </div>
       </div>

</form> smarty-debugger info: {$form_data}*Array (9)* *frozen* => *javascript* => /empty/ *attributes* => action="/index.php" method="post" na... *requirednote* => <span style="font-size:80%; color:#ff... *errors* => *Array (1)* *fields* => Invalid Username/Password! *hidden* => /empty/ *header* => *Array (1)* *login_header* => Login *fields* => *Array (11)* *name* => fields *value* => *Array (2)* *username* => rharding *password* => testing *type* => group *frozen* => *required* => *error* => *label* => <br /> *separator* => /empty/ *html* => <input size="15" maxlength="25" name=... *username* => *Array (8)* *name* => fields[username] *value* => rharding *type* => text *frozen* => *required* => *error* => *label* => Username *html* => <input size="15" maxlength="25" name=... *password* => *Array (8)* *name* => fields[password] *value* => testing *type* => password *frozen* => *required* => *error* => *label* => Password *html* => <input size="15" maxlength="25" name=... *login_button* => *Array (8)* *name* => login_button *value* => Login *type* => submit *frozen* => *required* => *error* => *label* => /empty/ *html* => <input name="login_button" value="Log...