The remote host is missing an update to htdig announced via advisory DSA 1429-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201429-1

Michael Skibbe discovered that htdig, a WWW search system for an intranet or small internet, did not adequately quote values submitted to the search script, allowing remote attackers to inject arbitrary script or HTML into specially crafted links. For the stable distribution (etch), this problem has been fixed in version 1:3.2.0b6-3.1etch1 For the old stable distribution (sarge), this problem was not present. For the unstable distribution (sid), this problem has been fixed in version 1:3.2.0b6-4. We recommend that you upgrade your htdig package.