one of the documented procedures in this installation of the ACS
ad_scope_return_warning   title   explanation   db
What it does:
if scope is not set in the topmost environment then public scope is assumed. if scope=group, it assumes that group_vars_set is set in the topmost environment. returns warning message properly formatted for appropriate scope. this procedure is appropriate for messages like not authorized to access this page.
Defined in: /web/philip/tcl/ad-scope.tcl

Source code:

    if { [uplevel [ad_scope_upvar_level] {info exists scope}] } {
	upvar [ad_scope_upvar_level] scope scope
    } else {
	set scope public

    switch $scope {
	public {
	    return [ad_return_warning $title $explanation]
	group {
	    upvar [ad_scope_upvar_level] group_vars_set group_vars_set
	    set group_id [ns_set get $group_vars_set group_id]
	    set group_name [ns_set get $group_vars_set group_name]
	    set group_admin_email [ns_set get $group_vars_set group_admin_email]
	    return [ug_return_warning $title $explanation $db $group_id $group_name $group_admin_email]
	user {
	    # this may be later modified if we allow users to customize the display of their pages
	    return [ad_return_warning $title $explanation]