package linux-image-2.6.31-19-generic 2.6.31-19.56 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

Binary package hint: grub

How do I do this?

E: dpkg was interrupted, you must manually run 'sudo dpkg --configure -a' to correct the problem.
E: _cache->open() failed, please report.

ProblemType: Package
Architecture: i386
Date: Thu Feb 4 22:17:01 2010
DistroRelease: Ubuntu 9.10
ErrorMessage: subprocess installed post-installation script returned error exit status 1
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release i386 (20091028.5)
Package: linux-image-2.6.31-19-generic 2.6.31-19.56
ProcVersionSignature: Ubuntu 2.6.31-17.54-generic
SourcePackage: grub
Title: package linux-image-2.6.31-19-generic 2.6.31-19.56 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1
Uname: Linux 2.6.31-17-generic i686