The remote host is missing an update to cacti announced via advisory DSA 1569-3.

https://secure1.securityspace.com/smysecure/catid.html?in=DSA%201569-3

Since the previous security update, the cacti package could no longer be rebuilt from the source package. This update corrects that problem. Note that this problem does not affect regular use of the provided binary packages (.deb). For reference the original advisory text follows. It was discovered that Cacti, a systems and services monitoring frontend, performed insufficient input sanitising, leading to cross site scripting and SQL injection being possible. For the stable distribution (etch), this problem has been fixed in version 0.8.6i-3.5.