Is there a way to make a store a "recognizable" name to each of the members of a group?

When I review the list of members in the group I created, the members are identified by their Yahoo user name. Some of them are not their real names, so it's hard to keep track of who they are. I'd like to be able to store a real name ociated with the Yahoo user iDs in the members page so it's easy to know who's who. Does anyone know how to do that?