Code Conversion Joomla 1.5 to Joomla 1.7/2.5
I am trying to convert this plugin to Joomla 1.7, as I don have extensive understanding of PHP I am not getting anywhere. Any kind of help is appreciated. 

URL of the plugin: http://extensions.joomla.org/extensions/content-sharing/mailing-a-newsletter-bridges/10400


    <?php
// no direct access
defined( '_JEXEC' ) or die( 'Restricted access' );

jimport( 'joomla.plugin.plugin' );

class plgSystemAutoresponder extends JPlugin
{
	
	function onUserAfterSave($user, $isnew, $succes, $msg)
	{
		
		//$mainframe->redirect("index.php?option=com_contact");//Put your new page URL here
		
		
		 global $mainframe;
		 

    


        // convert the user parameters passed to the event
        // to a format the external application
       $args = array();
		$args['username']	= $user['username'];
		$args['email'] 		= $user['email'];
		$args['fullname']	= $user['name'];
		$args['password']	= $user['password'];
		$email1 = $user['email'];
		$name1 = $args['username'];

		$email = $args['email'];
		$name = $args['username'];
		
		//load plugin parameters
		
		$plugin=&JPluginHelper::getPlugin('autoresponder');
            $pluginParams = new JParameter( $plugin->params );
			
			
		
		 $responderUrl = $this->params->get( 'responder_url' );
		 $MetaWebFormId = $this->params->get( 'meta_web_form_id');
		 $MetaSplitId = $this->params->get( 'meta_split_id' );
		 $Unit = $this->params->get( 'unit' );
		 $Redirect = $this->params->get( 'redirect' );
		 $MetaRedirectOnlist = $this->params->get( 'meta_redirect_onlist' );
		 $MetaAdtracking = $this->params->get( 'meta_adtracking' );
		 $MetaMessage = $this->params->get( 'meta_message' );
		 $MetaRequired = $this->params->get( 'meta_required' );
		 $MetaForwardVars = $this->params->get( 'meta_forward_vars' );
		

	$mainframe->redirect($responderUrl."?from=".$email."&name=".$name."&meta_web_form_id=".$MetaWebFormId."&meta_split_id="."&unit=".$Unit."&redirect=".$Redirect."&meta_redirect_onlist=".$MetaRedirectOnlist."&meta_adtracking=".$MetaAdtracking."&meta_message=".$MetaMessage."&meta_required=".$MetaRequired."&meta_forward_vars=".$MetaForwardVars);
                
	}
}
?>

I have updated the XML to Joomla 1.7. But Joomla 1.7 is giving error is line 38 and 54

Line 38:  `$pluginParams = new JParameter( $plugin->params );`
Line 54:  `$mainframe->redirect($responderUrl."?from=".$email."&name=".$name."&meta_web_form_id=".$MetaWebFormId."&meta_split_id="."&unit=".$Unit."&redirect=".$Redirect."&meta_redirect_onlist=".$MetaRedirectOnlist."&meta_adtracking=".$MetaAdtracking."&meta_message=".$MetaMessage."&meta_required=".$MetaRequired."&meta_forward_vars=".$MetaForwardVars);`
Code Conversion Joomla 1.5 to Joomla 1.7/2.5
===

I am trying to convert this plugin to Joomla 1.7, as I don have extensive understanding of PHP I am not getting anywhere. Any kind of help is appreciated. 

URL of the plugin: http://extensions.joomla.org/extensions/content-sharing/mailing-a-newsletter-bridges/10400


    <?php
// no direct access
defined( '_JEXEC' ) or die( 'Restricted access' );

jimport( 'joomla.plugin.plugin' );

class plgSystemAutoresponder extends JPlugin
{
	
	function onUserAfterSave($user, $isnew, $succes, $msg)
	{
		
		//$mainframe->redirect("index.php?option=com_contact");//Put your new page URL here
		
		
		 global $mainframe;
		 

    


        // convert the user parameters passed to the event
        // to a format the external application
       $args = array();
		$args['username']	= $user['username'];
		$args['email'] 		= $user['email'];
		$args['fullname']	= $user['name'];
		$args['password']	= $user['password'];
		$email1 = $user['email'];
		$name1 = $args['username'];

		$email = $args['email'];
		$name = $args['username'];
		
		//load plugin parameters
		
		$plugin=&JPluginHelper::getPlugin('autoresponder');
            $pluginParams = new JParameter( $plugin->params );
			
			
		
		 $responderUrl = $this->params->get( 'responder_url' );
		 $MetaWebFormId = $this->params->get( 'meta_web_form_id');
		 $MetaSplitId = $this->params->get( 'meta_split_id' );
		 $Unit = $this->params->get( 'unit' );
		 $Redirect = $this->params->get( 'redirect' );
		 $MetaRedirectOnlist = $this->params->get( 'meta_redirect_onlist' );
		 $MetaAdtracking = $this->params->get( 'meta_adtracking' );
		 $MetaMessage = $this->params->get( 'meta_message' );
		 $MetaRequired = $this->params->get( 'meta_required' );
		 $MetaForwardVars = $this->params->get( 'meta_forward_vars' );
		

	$mainframe->redirect($responderUrl."?from=".$email."&name=".$name."&meta_web_form_id=".$MetaWebFormId."&meta_split_id="."&unit=".$Unit."&redirect=".$Redirect."&meta_redirect_onlist=".$MetaRedirectOnlist."&meta_adtracking=".$MetaAdtracking."&meta_message=".$MetaMessage."&meta_required=".$MetaRequired."&meta_forward_vars=".$MetaForwardVars);
                
	}
}
?>

I have updated the XML to Joomla 1.7. But Joomla 1.7 is giving error is line 38 and 54

Line 38:  `$pluginParams = new JParameter( $plugin->params );`
Line 54:  `$mainframe->redirect($responderUrl."?from=".$email."&name=".$name."&meta_web_form_id=".$MetaWebFormId."&meta_split_id="."&unit=".$Unit."&redirect=".$Redirect."&meta_redirect_onlist=".$MetaRedirectOnlist."&meta_adtracking=".$MetaAdtracking."&meta_message=".$MetaMessage."&meta_required=".$MetaRequired."&meta_forward_vars=".$MetaForwardVars);`