It's working for at least one aolserver 4.5.1 on freebsd using this in nsd.tcl:
#
# Special HTTP pages
#
ns_param NotFoundResponse "/global/404.adp"
ns_param ServerBusyResponse "/global/busy.html"
ns_param ServerInternalErrorResponse "/global/error.html"
#---------------------------------------------------------------------
#
# ADP (AOLserver Dynamic Page) configuration
#
#---------------------------------------------------------------------
ns_section ns/server/${server}/adp
ns_param map /*.adp ;# Extensions to parse as ADP's
# ns_param map "/*.html" ;# Any extension can be mapped
ns_param enableexpire false ;# Set "Expires: now" on all ADP's
ns_param enabledebug $debug ;# Allow Tclpro debugging with "?debug"
ns_param defaultparser fancy
ns_section ns/server/${server}/adp/parsers
ns_param fancy ".adp"
ns_section ns/server/${server}/redirects
ns_param 404 "/global/404.adp"
ns_param 403 "/global/forbidden.html"