Making use of D-Bus in Gajim Gajim package comes with a command, called gajim-remote with which you can execute remote actions.

gajim-remote toggle_roster_appearance

this will show/hide your roster

gajim-remote show_next_pending_event

and if you have unread message, a chat dialog containg one of the awaiting messages will popup

Lots of other things are of course possible:

Using D-Bus notifications

Here's an example python script to monitor dbus and do something when notified via dbus by gajim.  script

This script talks to the water plugin from  beryl and creates a catchy water ripple notification on incoming messages:  gajim2beryl.py . You can see the script in action in this little  demo screencast hosted on youtube.

To use script with  Compiz Fusion run it's modified version .

Disabling D-Bus-related capabilities of Gajim

You can turn off the ability to remote control Gajim. The setting you want is remote_control.

You can turn off the ability to use notification daemon (if there) cool notification popups. The setting you want is use_notif_daemon.

You can do this by setting you want to False in Preferences Window, Advanced Tab, Open Advanced Editor. DBUS & KDE KDE 3.4.3 doesn't appear to start a Dbus instance for the user by default. Adding the .bashrc lines from above to a ~/.kde/env/dbus.sh seems to the trick. This is under Gentoo, with /etc/init.d/dbus running.