cannot erase a blu ray rewritable

[Alistair Buxton]

To reproduce:

1. Get a BD-RE and burn some ISO to it.
2. Start brasero and select tools->blank
3. Select the disc (probably already selected) and continue.

The disc is ejected and reinserted a couple of times. Then finally it is ejected and a message box appears saying "disc successfully blanked." However, upon reinserting the disc all the previous contents are still present.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: brasero 3.4.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-21.34-generic 3.2.13
Uname: Linux 3.2.0-21-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.0-0ubuntu1
Architecture: amd64
Date: Wed Apr 4 02:23:09 2012
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Beta amd64 (20120328)
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=xterm
 PATH=(custom, user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: brasero
UpgradeStatus: No upgrade log present (probably fresh install)