even renaming the plugin file and putting it into mu-plugins/ doesn’t work.
the new menu under the dashboard is created but the old one remains 
might have a hint, this is from my error log:
`[Mon Jul 25 12:42:55 2011] [warn] [client 145.253.32.107] mod_fcgid: stderr: PHP Warning: Cannot modify header information – headers already sent by (output started at /var/www/clients/clientxx/webxx/web/wp-content/plugins/grunion-contact-form/grunion-contact-form.php:682) in /var/www/clients/clientxx/webxx/web/wp-includes/pluggable.php on line 934, referer: http://zice.ro/wp-admin/
`