kvera

To me, (not on MU), it occurs when your’re viewing the site without being logged-in. Because when a user isn’t logged in the Global $wp_roles is empty.

As a workaround, i had edited the user-role-editor.php,
@line: 181 you’ll have the ure_init() function.
inside of it, the test for: if (!$role->has_cap(URE_KEY_CAPABILITY)) {
i’d put that entire block inside a if, to test if we had a user logged in.

I’ve found the error.
It was on a custom login widget from the theme i use. The widget was using a parameter with the same name as the wordpress uses. Changed the name of the parameter and reported to the theme developer.

Thanks for the help Ipstenu ??

you can use one plugin to do this.
Cimy User Extra Fields allow you manage WordPress user fields and create new ones, even to show these these new fields in the registration form.

I Use it in at least 2 Blogs, and i’m satisfied.

Tryed, but… nothing.