Upgrading package fails

[Hassan El Jacifi]

Binary package hint: udev

Package: udev
Version: 093-0ubuntu1

When I tried to upgrade, dpkg croaked and bailed out with:

Setting up udev (093-0ubuntu1) ...
/var/lib/dpkg/info/udev.postinst: line 82: my_persistent_disk_rules: command not found
dpkg: error processing udev (--configure):
 subprocess post-installation script returned error exit status 127
Errors were encountered while processing:
 udev

-- System Information:
Debian Release: testing/unstable
  APT prefers edgy-updates
  APT policy: (500, 'edgy-updates'), (500, 'edgy-security'), (500, 'edgy'), (500, 'dapper-security')
Architecture: i386 (i686)
Shell: /bin/sh linked to /bin/bash
Kernel: Linux 2.6.15-23-686
Locale: LANG=C, LC_CTYPE=C (charmap=ANSI_X3.4-1968)

Versions of packages udev depends on:
ii grepmap 1.1.0-1 Parse module map files produced by
ii initramfs-tools 0.40ubuntu32 tools for generating an initramfs
ii libc6 2.4-1ubuntu4 GNU C Library: Shared libraries
ii libselinux1 1.30-1 SELinux shared libraries
ii libsepol1 1.12-1 Security Enhanced Linux policy lib
ii module-init-tools 3.2.2-3ubuntu1 tools for managing Linux kernel mo

udev recommends no packages.

-- no debconf information