It's a hassle to write he/she, him/her, his/her when you refer to a member whose gender is unknown. So I suggest gender be added to the profile page of a member.
EDIT(Aug. 19, 2003) Since some members don't want to make their gender public, I would like to suggest the following feature request.
There be the following options regarding gender of a member in the profile page.
If you choose the option 3, you are not supposed to complain when you are referred to he(or she).
Remark The option 3 is default. This prevents people from guessing that a person who chooses it is female.