Trillian BDC. Download the compiled application here. User documentation in the wiki.
#Trillian BDC
Keep track of your friends' birthdays. "Birthday Calendar" (BDC) is a plugin for Trillian.
Trillian is a gratis multiprotocol instant messaging application that is extendable by plugins. The BDC plugin was the most popular plugin for many consecutive months, and is still a popular download among Trillian plugins.
This plugin does not send cards or flowers on contacts's birthdays, nor does it apologize on your behalf when you forget about birthdays after all.
You are hereby encouraged to use this plugin only with a legal and registered Pro version of Trillian.
Download the plugin here.