The remote host is missing an update to icedove announced via advisory DSA 2297-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%202297-1

Several vulnerabilities have been discovered in Icedove, an unbranded version of the Thunderbird mail/news client. CVE-2011-0084 regenrecht discovered that incorrect pointer handling in the SVG processing code could lead to the execution of arbitrary code. CVE-2011-2378 regenrecht discovered that incorrect memory management in DOM processing could lead to the execution of arbitrary code. CVE-2011-2981 moz_bug_r_a_4 discovered a Chrome privilege escalation vulnerability in the event handler code. CVE-2011-2982 Gary Kwong, Igor Bukanov, Nils and Bob Clary discovered memory corruption bugs, which may lead to the execution of arbitrary code. CVE-2011-2983 shutdown discovered an information leak in the handling of RegExp.input. CVE-2011-2984 moz_bug_r_a4 discovered a Chrome privilege escalation vulnerability. As indicated in the Lenny (oldstable) release notes, security support for the Icedove packages in the oldstable needed to be stopped before the end of the regular Lenny security maintenance life cycle. You are strongly encouraged to upgrade to stable or switch to a different mail client. For the stable distribution (squeeze), this problem has been fixed in version 3.0.11-1+squeeze4. For the unstable distribution (sid), this problem has been fixed in version 3.1.12-1. We recommend that you upgrade your iceweasel packages.