Even though admin-6.x-1.0-beta5 isn't "compliant" with the proper way to implement a drupal 6 admin theme nowadays, my clients absolutely ADORE admin-6.x-1.0-beta5 over any other admin theme I've shown them. I use a lot of contributed modules and I've noticed that on some admin pages of these modules, like revisioning, node access, menu block, the site reverts back to the default theme the end user sees.

I've rolled a custom module to force some of these pages to use the admin theme when you are using admin-6.x-1.0-beta5.

Right now, I have it hardcoded to check for certain modules, but I think this would be a useful feature addon to admin-6.x-1.0-beta5, where a developer could add a list of pages that don't use the admin theme but should. Then it reads those pages from cache or something and calls _admin_init_theme();

Here's the code, just calling hook_init()

function cv_admin_theme_helper_init(){
	//For node access module
	if(arg(0) == "node" && arg(2) == "grant"){
			  _admin_init_theme();
	}
	
	//For revisioning
	if(arg(0) == "node" && arg(2) == "revisions"){
		  if(arg(4) != "view"){
			  _admin_init_theme();
		  }
	}
	
	//For add menu block page
	if(arg(0) == "admin" && arg(3) == "add-menu-block"){
			  _admin_init_theme();
	}
}