RCVD_IN_VALIDITY_RPBL_BLOCKED

I'm seeing this error over and over in my logs over the last few weeks:

spamd: check: dns_block_rule RCVD_IN_VALIDITY_RPBL_BLOCKED hit, creating 
/root/.spamassassin/dnsblock_bl.score.senderscore.com (This means DNSBL 
blocked you due to too many queries. Set all affected rules score to 0, 
or use "dns_query_restriction deny bl.score.senderscore.com" to disable 
queries)

I did try to disable this in root's local.cf but the error continues.

I am using my own proper bind DNS server running on my host to query, 
not forwarding requests to Linode or google.  My host is at linode 
though so I wonder if the ip address of my server I'm in got flagged 
some other network neighbor or if my spamd really did query too many 
times.  But after several weeks, the error persists.

Any ideas?  Thanks.

Michael Grant