I'm trying to code a module that sets the theme for a class of users by (1) using HTTP BASIC AUTH, and (2) changing the theme according to what BASIC AUTH user they log in as; this is used in a two tier login system. This is a 4.6 site, and I'm trying to do what og.module did in 4.6 time: set the global $custom_theme to the name of the theme I want. I'm doing this in my menu handler in the uncached section of the handler. The first time someone calls a theming function, init_theme() gets called, and init_theme is seeing the right value for $custom_theme. But if I select anything but the current default theme, the page renders in a very weird fashion: {head} {styles} {_BLOCK_.header.logo} {_BLOCK_.header.site_name} {secondary_links} {primary_links} {_BLOCK_.header.blocks} {_BLOCK_.header.title} {submitted} {content} {_BLOCK_.footer.message} Obviously, something isn't set up right. I've seen this happen before, but not with my own code. Does anyone know what's going on here? Thanks, Rob