one of the documented procedures in this installation of the ACS
sec_lookup_property   browser   id   module   name
What it does:
Used as a helper procedure for util_memoize to look up a particular property from the database. Returns [list $property_value $secure_p].
Defined in: /web/philip/packages/acs-core/security-procs.tcl

Source code:

    set kind [ad_decode $browser "t" "browser" "session"]

    set db [ns_db gethandle log]
    set selection [ns_db 0or1row $db "
        select property_value, secure_p
        from sec_${kind}_properties
        where ${kind}_id = '[DoubleApos $id]'
        and module = '[DoubleApos $module]'
        and property_name = '[DoubleApos $name]'
    if { $selection == "" } {
	ns_db releasehandle $db
	return ""

    ns_db releasehandle $db
    return [list $property_value $secure_p]