Crontab & Gnome-Scheduler simply do not work in Lubuntu

[Pierre]

Crontab & Gnome-Scheduler simply do not work in Lubuntu 11.10. Not sure if it ever worked.
Crontab & Gnome-Scheduler simply do not work in Lubuntu. E.g.: Tried testing with opening leafpad 35 min. after the hour using gnome-scheduler.

In crontab -e:
# For more information see the manual pages of crontab(5) and cron(8)
#
# m h dom mon dow command
35 * * * * /usr/bin/leafpad # JOB_ID_1

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: cron 3.0pl1-116ubuntu3
ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4
Uname: Linux 3.0.0-12-generic i686
ApportVersion: 1.23-0ubuntu4
Architecture: i386
Date: Thu Nov 17 18:39:18 2011
InstallationMedia: Lubuntu 11.10 "Oneiric Ocelot" - Release i386 (20111012)
ProcEnviron:
 LANGUAGE=en_CA:en
 LANG=en_CA.UTF-8
 SHELL=/bin/bash
SourcePackage: cron
UpgradeStatus: No upgrade log present (probably fresh install)

[Pierre (pierrewinnipeg)]

Adding information. In var/log/syslog, I get:

(grandchild #2597 failed with exit status 255)
(CRON) info (No MTA installed, discarding output)

[Pierre (pierrewinnipeg)]

Solved.

30 19 * * * DISPLAY=:0.0 /usr/bin/leafpadhttps://bugs.launchpad.net/bugs/891869

To open a program on your desktop, you need tell cron what display to use. Not obvious!!!

Details at this thread:
http://ubuntuforums.org/showthread.php?t=1823285

[Pierre (pierrewinnipeg)]

Note: THIS SHOULD BE IN THE MANUAL!

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Launchpad Janitor (janitor)]

This bug was fixed in the package cron - 3.0pl1-133ubuntu1

---------------
cron (3.0pl1-133ubuntu1) eoan; urgency=low

  * Merge from Debian unstable. Remaining changes:
    - debian/control:
      + Move MTA to Suggests field.
    - d/cron.default: change to a deprecated message to make it clear
      that the file is no longer in use.
  * Dropped changes, no longer needed:
    - Drop upstart system jobs; transition completed as of 18.04.
    - Handle /etc/init.d/cron symlink→ real file transition; completed as of
      18.04.

cron (3.0pl1-133) unstable; urgency=medium

  * SECURITY: Fix bypass of /etc/cron.{allow,deny} on failure to open
    If these files exist, then they must be readable by the user executing
    crontab(1). Users will now be denied by default if they aren't.
    (LP: #1813833)
  * SECURITY: Fix for possible DoS by use-after-free
    A user reported a use-after-free condition in the cron daemon, leading to a
    possible Denial-of-Service scenario by crashing the daemon.
    (Closes: #809167)
  * SECURITY: DoS: Fix unchecked return of calloc()
    Florian Weimer discovered that a missing check for the return value of
    calloc() could crash the daemon, which could be triggered by a very
    large crontab created by a user.
  * Enforce maximum crontab line count of 1000 to prevent a malicious user
    from creating an excessivly large crontab. The daemon will log a warning
    for existing files, and crontab(1) will refuse to create new ones.
  * Add d/NEWS altering to the new 1000 lines limit.
  * Move /var/run/crond.reboot to /run/crond.reboot.
  * crontab.5: Reverse the info on tilde expansion. When setting PATH, most
    shells will not expand a tilde. Thanks, Tim Landscheidt, for the analysis.
    (Closes: #801328)
  * Fixes for numerous man page issues. Remove trailing whitespace, use proper
    escapes, etc. Thanks, Bjarni Ingi Gislason! (Closes: #893575, #893579)
  * crontab.1: Drop duplicate DIAGNOSTICS header.
  * daemon: Only support the 'x' debug option in debug builds.

cron (3.0pl1-132) unstable; urgency=medium

  [ Christian Kastner ]
  * postinst: Properly test for regular file
    cron.postinst checked for a regular file by parsing the stat output,
    instead of simply relying on test(1)
  * Mark package cron as Multi-Arch: foreign (Closes: #878363)

  [ Stéphane Blondon ]
  * Add forgotten '\n' to a line in the crontab header (Closes: #898119)

cron (3.0pl1-131) unstable; urgency=medium

  [ Boyuan Yang ]
  * debian/control:
    - Merge duplicated build-dependency entry for debhelper
    - Update Vcs-* fields and use git repo under Salsa Debian group
      (Closes: #913484)
    - Add dependency to sensible-utils (Closes: #913483)
  * debian/rules: Do not explicitly invoke dpkg-architecture for architecture
    variables. Instead we are now using /usr/share/dpkg/architecture.mk to
    provide them

  [ Bjarni Ingi Gislason ]
  * crontab.1: Some format fixes in the manual. (Closes: #893576)

  [ Christian Kastner ]
  * d/control:
    - Switch Build-Depends from debhelper to debhelper-compat
    - Add Rules-Requires-Root: no
      We don't need (fake)root for building the package
    - Drop ancient dpkg...