See for instance http://drupal.org/search/user_search/louboutin even with an unprivileged account like mine. Most of the results are disabled accounts.
I can confirm this.
It would be nice to see this fixed, but I am not sure where the actual issue is.
If I get a pointer I might work on this.
We just use core's user search. If D7 core isn't flexible to override this cleanly, we can either work on getting a patch in core, or override it with a View, or even consider https://drupal.org/project/apachesolr_user.
This will not be fixed in 6.x.
Actually no: We use user_search.module which seems to be a d.o specific hack made by David. :p
It is rather similar to the user core search, though, the bug is present in both. Weird.
This is fixed in D7 though, I guess it will auto-fix with the upgrade.
Since it works in D7.
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