WordPress MU

If I add fields to wp_users in the database, how can I add the necessary input fields into the registration process?

For example:

user_location
user_image
user_interests
user_resume
user_phonenumber

etc.

I've looked at wp-signup.php and wp-register.php, but can't figure it out. Has anyone else done this? Or would it mess up the system?

I would have guessed someone would have done an extra fields plugin by now for regular WordPress.

I've found these plugins:

usermeta
userextra

These apparently use a seperate usermeta table. I'm looking for a solution that keeps all the user data logically in one place.

This plugin looks very promising:
WP-Members

There are already plugins that extend the existing WordPress users table to add user customizable fields like address info, etc. There are plugins to expand on the restriction of posts to members only. ... Unfortunately, none of these fit the bill for a client application that had come up, so I had to develop one from scratch. What was left over from that is being released as a plugin.

I'd like to know which plugins he's talking about.

Going to try out WP-Members now...

There is also http://www.cimatti.it/blog/2007/02/12/cimy-user-extra-fields-for-wordpress-21/

untested for MU.

Cimy doesn't work in MU for the sub-blogs (at least with sub-domains).

I'm now on the hunt. Again.

I know it's been done on chickspeak.com, but I think the plugin is private.

However the odd thing is I don't know how the extra fields in the profile is displayed on the site, like I don't see a profile page.

I'm lucky enough to have been able to sign up. (It's restricted to female college students with college e-mail addresses.)

Maybe a good idea would be to work with the Cimy plugin, figure out why it's not working (Do note that you don't mention in your post why it's not working or where the issue is.) and modify the code.

Cimy works for me. I'll document on Codex.

http://codex.wordpress.org/WPMU_Cimy_Extra_Fields_Plugin

The MU version above will not work anymore after the 1.0.1 version... there has been changed a lot in the plugin.