POP3 logon attempts

Hi,
some of our POP3 servers got DoSed cause of massive password probes against following accounts:

admin
backup
data
master
oracle
root
server
sybase
test
user
web
webmaster

Does someone know a tool which will brute force these accounts?

-- 
Tom Fischer                              Tom.Fischer@rus.uni-stuttgart.de
RUS-CERT University of Stuttgart       Tel:+49 711 685-8076 / -5898 (fax)
Allmandring 30, D-70550 Stuttgart           
http://cert.uni-stuttgart.de/

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