php fatal errors on uninstall

I had the following errors in my php error log after uninstalling backupwordpress.

[27-Apr-2013 21:46:17] PHP Fatal error:  Uncaught exception 'Exception' with message 'You can only delete directories inside your WordPress installation' in /home/user/public_html/mydomain.com/wp-content/plugins/backupwordpress/functions/core.php:224
Stack trace:
#0 /home/user/public_html/mydomain.com/wp-content/plugins/backupwordpress/uninstall.php(23): hmbkp_rmdirtree('/')
#1 /home/user/public_html/mydomain.com/wp-admin/includes/plugin.php(851): include('/home/user/...')
#2 /home/user/public_html/mydomain.com/wp-admin/includes/plugin.php(727): uninstall_plugin('backupwordpress...')
#3 /home/user/public_html/mydomain.com/wp-admin/plugins.php(318): delete_plugins(Array)
#4 {main}
  thrown in /home/user/public_html/mydomain.com/wp-content/plugins/backupwordpress/functions/core.php on line 224
[27-Apr-2013 21:47:07] PHP Fatal error:  Uncaught exception 'Exception' with message 'You can only delete directories inside your WordPress installation' in /home/user/public_html/mydomain.com/wp-content/plugins/backupwordpress/functions/core.php:224
Stack trace:
#0 /home/user/public_html/mydomain.com/wp-content/plugins/backupwordpress/uninstall.php(23): hmbkp_rmdirtree('/')
#1 /home/user/public_html/mydomain.com/wp-admin/includes/plugin.php(851): include('/home/user/...')
#2 /home/user/public_html/mydomain.com/wp-admin/includes/plugin.php(727): uninstall_plugin('backupwordpress...')
#3 /home/user/public_html/mydomain.com/wp-admin/plugins.php(318): delete_plugins(Array)
#4 {main}
  thrown in /home/user/public_html/mydomain.com/wp-content/plugins/backupwordpress/functions/core.php on line 224

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