I'm not sure if this just happens to me, or if management is aware of it. But in the User CP, every time I change some info (for example Bio) my birth date is reset and my age is not shown on my profile. Each time I must select my date of birth from the drop down boxes because they go to ---- each time.
It's something to do with your browser's cookies. Whenever I update my profile in Firefox I have to delete Steam ID and Password Reset and in IE I don't have to.