google talk

I just switched from a BlackBerry to the DroidX and so far im loving Android. On my blackberry i used gtalk for almost everything and the one nice thing about it was i was able to set an alert to notify me when a certain person would come online. I cant seem to find that option in the android version, am i just missing it somewhere? If not, is there some other sort of messaging application that i can use gtalk in and receive notifications when a certain person comes online?