title: Grails 2.0 and PayPal plugin
body: <p>I've installed the newest Grails <code>PayPal-Plugin (0.6.4)</code> and got the following error:</p>
  
  <pre><code>Problems occurred (un)installing plugins. See details for more information
  ------System.out:-----------
  | Loading Grails 2.0.0
  | Configuring classpath.
  | Environment set to development.....
  | Compiling 97 source files
  | Compiling 97 source files.
  | Error Compilation error: startup failed:
  C:\Users\username\.grails\2.0.0\projects\projectname\plugins\paypal-0.6.4\grails-app\controllers\org\grails\paypal\PaypalController.groovy: -1: The return type of java.lang.Object notify() in org.grails.paypal.PaypalController is incompatible with void notify() in java.lang.Object
  . At [-1:-1]  @ line -1, column -1.
  1 error
  ------System.err:-----------
  </code></pre>
  
  <p>I fixed it by renaming <code>notify()</code> into <code>notifyPaypal()</code> => <a href="https://stackoverflow.com/questions/8492661/error-paypal-plugin-on-grails-2-0-0-rc3">Error PayPal plugin on grails 2.0.0.RC3</a></p>
  
  <p>But the plugin seems to disturb springSecurity because I got the following error if I try to login:</p>
  
  <pre><code>| Error 2012-02-05 21:42:07,245 ["http-bio-8080"-exec-8] ERROR [/projectname].[default]  - Servlet.service() for servlet [default] in context with path [/projectname] threw exception
  Message: The specified user domain class 'Person' is not a domain class
  </code></pre>
  
  <p>How can I fix it?</p>