Linux: notification area

I am using Mandriva 2007. Since I installed that, I could not find icons that I launched every time. For example, I start "scim" (Smart Chinese Input Method), no any icon shows up. Also, 'network appel', it is always there (been started) but I don't know where it is (open its window). They are started, but because I didn't put a 'notification area' on the panel, they are not seen!! Today I suddenly realized that! And more icons running are over there such as 'network', 'power management', ...