Comment 2 for bug 1015435

Looks to be casper related:

run-parts: executing /etc/kernel/postinst.d/initramfs-tools 3.2.0-25-generic /boot/vmlinuz-3.2.0-25-generic
update-initramfs: Generating /boot/initrd.img-3.2.0-25-generic
E: /usr/share/initramfs-tools/hooks/casper failed with return 1.
update-initramfs: failed for /boot/initrd.img-3.2.0-25-generic with 1.
run-parts: /etc/kernel/postinst.d/initramfs-tools exited with return code 1
Failed to process /etc/kernel/postinst.d at /var/lib/dpkg/info/linux-image-3.2.0-25-generic.postinst line 1010.
dpkg: error processing linux-image-3.2.0-25-generic (--configure):
 subprocess installed post-installation script returned error exit status 2