This bug was fixed in the package virtualbox - 4.1.12-dfsg-2ubuntu0.1
--------------- virtualbox (4.1.12-dfsg-2ubuntu0.1) precise-proposed; urgency=low
* Fix vboxnet device unregistration on kernel >= 3.2.18. (LP: #1009156) - Add 37-fix-unregister-netdevice.patch, backported from upstream. -- Felix Geyer <email address hidden> Tue, 12 Jun 2012 22:59:06 +0200
This bug was fixed in the package virtualbox - 4.1.12- dfsg-2ubuntu0. 1
--------------- dfsg-2ubuntu0. 1) precise-proposed; urgency=low
virtualbox (4.1.12-
* Fix vboxnet device unregistration on kernel >= 3.2.18. (LP: #1009156) unregister- netdevice. patch, backported from upstream.
- Add 37-fix-
-- Felix Geyer <email address hidden> Tue, 12 Jun 2012 22:59:06 +0200