Distro: Fedora 16
Version: PackageKit 0.6.19

Nautilus has a PackageKit integration, which is enabled by default in Fedora 16.
It works like this:
- user double clicks on a file with no installed applications to open it
- if the PK integration is enabled, nautilus will start an async gdbus call to create a proxy for the org.freedesktop.PackageKit.Modify interface. This has the double purpose of both probing PK availability on the system and creating the proxy object to make the actual call to the InstallMimeTypes DBus method later

  g_dbus_proxy_new_for_bus (G_BUS_TYPE_SESSION,
                            G_DBUS_PROXY_FLAGS_NONE,
                            NULL,
                            "org.freedesktop.PackageKit",
                            "/org/freedesktop/PackageKit",
                            "org.freedesktop.PackageKit.Modify",
                            NULL,
                            pk_proxy_appeared_cb,
                            parameters_install);

- if PK is available on the system, the proxy will be created successfully and a message dialog will be shown asking the user if she wants to find an application in the repos to handle the file

The bug here is that the call to g_dbus_proxy_new_for_bus() seems to take a really long time (about a minute or so) if PK has just be spawned for the first time (I guess it updates its package cache), which shouldn't really be the case. Is PK blocking its mainloop or doing something which prevents the DBus activation to return immediately?

The visible effect is clicking on a file with no applications installed to handle it yields no action at all under these circumstances (and a dialog will appear out of the blue one minute or more later if Nautilus is still running).