Can user-agents be listed together, followed by their common rules like so in a robots.txt?
User-agent: Googlebot
User-agent: ia_archiver #Alexa
User-agent: BingPreview #Microsoft
User-agent: bingbot #Microsoft
User-agent: MSNBot #Microsoft
User-agent: Slurp #Yahoo
User-agent: Ask Jeeves/Teoma #Ask
Disallow: /adm30_buds/
user-agent: *
followed by the disallow? Is the list of "allowed" user-agents longer than the list that you want to disallow?