The remote host is missing an update to pdns-recursor announced via advisory DSA 1968-2.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201968-2

It was discovered that pdns-recursor, the PowerDNS recursive name server, contains a cache poisoning vulnerability which may allow attackers to trick the server into serving incorrect DNS data (CVE-2009-4010). This DSA provides a security update for the old stable distribution (etch), similar to the previous update in DSA-1968-1. (Note that the etch version of pdns-recursor was not vulnerable to CVE-2009-4009.) Extra care should be applied when installing this update. It is an etch backport of the lenny version of the package (3.1.7 with security fixes applied). Major differences in internal domain name processing made backporting just the security fix too difficult. For the old stable distribution (etch), this problem has been fixed in version 3.1.4+v3.1.7-0+etch1. We recommend that you upgrade your pdns-recursor package.