Kopete: is there a way to disable desktop notification (the OSD Notify popups)?
Goto settings -> Notification, and uncheck popup notifications for all.
open kopete window then go to settings>Configure Notifications and select what you want kopete put in pop-ups xD
there’s also alternative notification system called Colibri
you can install it easy:
apt-get install colibri
IMHO it’s less annoying