The remote host is missing an update to ncompress announced via advisory DSA 2074-1.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%202074-1

Aki Helin discovered an integer underflow in ncompress, the original Lempel-Ziv compress/uncompress programs. This could lead to the execution of arbitrary code when trying to decompress a crafted LZW compressed gzip archive. For the stable distribution (lenny), this problem has been fixed in version 4.2.4.2-1+lenny1. For the testing (squeeze) and unstable (sid) distribution, this problem has been fixed in version 4.2.4.3-1. We recommend that you upgrade your ncompress package.