Admin Views Undefined property: views_plugin_display_system::$display_handler

I am using the following modules:
admin_menu 7.x-3.0-rc1
views 7.x-3.1
page_title 7.x-2.5

The full text of the error message is:
Notice: Undefined property: views_plugin_display_system::$display_handler in views_page_title_pattern_alter() (line 48 of /Users/jonathan/Sites/laphil/drupal/sites/all/modules/contrib/page_title/modules/views.page_title.inc).
Notice: Trying to get property of non-object in views_page_title_pattern_alter() (line 48 of /Users/jonathan/Sites/laphil/drupal/sites/all/modules/contrib/page_title/modules/views.page_title.inc).

This message appears on any view using the System display handler.

At first I thought this was an issue caused by the page_title module, since that is where this error occurs, but after reading this issue http://drupal.org/node/1099792, and looking closer at the error message, it looks like views_get_page_view() is expecting the view object, but for some reason the System display handler is being returned instead.