Bug#449473: Workaround

[Epikuro]

For anyone still fighting this bug: ftp-master.debian.org is currently
down, so packages cannot propagate from unstable into testing.
  http://lists.debian.org/debian-infrastructure-announce/2007/11/msg00001.html

The workaround is just to install the unstable version of XFWM:
  http://lwn.net/Articles/258049/
It can be downloaded from here:
  http://packages.debian.org/sid/xfwm4

Cheers,

Epikuro.