update-grub does not detect some installed systems

[Cristian Arezzini]

Binary package hint: grub2

Testing this on a fully updated Natty beta. Running update-grub (from the Natty installer, or after a kernel upgrade, or manually) doesn't detect the system I have installed on my sda11 partition (it's a Maverick system, my main production system). It detects correctly another "experimental" Ubuntu system, and the Vista partition.
If I manually mount the sda11 partition somewhere, and then manually run "sudo update-grub", then everything works as expected and it detects my Maverick install.
My partitioning is a little complex (I have 4 different Linux systems, plus a Windows system, plus 4 separate data partitions) but this has always worked fine with previous releases of Ubuntu.

My release:
cristian@cristian-HP-Pavilion-dv2700-Notebook-PC:~$ lsb_release -rd
Description: Ubuntu Natty (development branch)
Release: 11.04

Grub version:
1.99~rc1-8ubuntu1

What I expect to happen:
I expect, when running upgrade-grub (or when installing Natty, for that matter) that all my installed system are detected.

What happens instead:
My Maverick system on sda11 isn't detected. I have to manually mount sda11 somewhere and then re-run update-grub to have it detected.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: grub2 (not installed)
ProcVersionSignature: Ubuntu 2.6.38-7.39-generic 2.6.38
Uname: Linux 2.6.38-7-generic i686
NonfreeKernelModules: nvidia wl
Architecture: i386
Date: Mon Apr 4 18:12:42 2011
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha i386 (20110302)
ProcEnviron:
 LANGUAGE=en_US:en
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: grub2
UpgradeStatus: No upgrade log present (probably fresh install)

[Cristian Arezzini (macavity80)]

I made a mistake in the above description. The Maverick system that is not detected is not at sda11, but at sda2. The system that is present at sda11 is detected correctly. Everything else in the description above is correct.