Form API select type generates errors for some options arrays

When trying to fix a theme problem I ran into the following situation with the form api. With certain sets of data in the #options array inside a select state would cause the form api to blow up throwing errors. If you change the system_user function as described in node/35225 it generates the following errors.

warning: array_keys(): The first argument should be an array in c:\documents and settings\ccourtney\workspace\ea web site\includes\form.inc on line 31.

warning: array_filter(): The first argument should be an array in c:\documents and settings\ccourtney\workspace\ea web site\includes\form.inc on line 31.

warning: Invalid argument supplied for foreach() in c:\documents and settings\ccourtney\workspace\ea web site\includes\form.inc on line 302.