switch theme to roots and get logged out on every page change

(please edit the title from "them" to "theme" -- thanks)

This is strange, as I am surprised this is happening to me and not others.

When I switch the theme to "commons roots" I get logged out and have to log back in for each page. I can't change the theme using Admin or /admin/build/themes. I have the same problem on more than one Commons install--different domains and virtual hosts on the same server.

Changing variables: theme_default: s:15:"commons_connect"; and clearing the cache fixed the site and the continual logout problem is gone.

Also, changing the theme at the database and changing to /admin/settings/performance (logging on each page change) changed the theme. Likely changing to ../themes would have worked after making the DB variable change.