automessage fatal error: undefined methode: WP_user

Hi Team,

Since the update of WP 3.2 we have a problem with the AutoMessage plugin.

When an user will activate his website by the link in the e-mail he will get this error:
See attachment

So the website isn't activated.

When I deactivate the plugin AutoMessage the process works fine, but I love to use the AutoMessage.

Please, could you help us?

thank you in advance!