RBL resource to check entire netblock

[greg whynott <greg.whynott () gmail com>]

Hello,

I am wanting to purchase a /22 from one of the online auction sites
(Hilco).   Before we move ahead with it I wanted to check the history of
IPs within the allocation.    I find many sites where you can enter 1 IP to
do a check but they don't seem to accept subnets to check.

Are you aware of any services which could tell us if a /22 is clean or not?
 my google foo is weak.

thank you,
greg