jokosher freezes when I try to delete an instrument

Binary package hint: jokosher

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OS INFO

Description: Ubuntu 10.04.1 LTS
Release: 10.04
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PACKAGE INFO

jokosher:
  Installé : 0.11.5-1ubuntu1
  Candidat : 0.11.5-1ubuntu1
 Table de version :
 *** 0.11.5-1ubuntu1 0
        500 http://fr.archive.ubuntu.com/ubuntu/ lucid/universe Packages
        100 /var/lib/dpkg/status
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I tried to delete an instrument with a audio file (.mp4 format) in the timeline, then Jokosher has a heavy freeze !

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: jokosher 0.11.5-1ubuntu1
ProcVersionSignature: Ubuntu 2.6.32-24.42-generic 2.6.32.15+drm33.5
Uname: Linux 2.6.32-24-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Thu Sep 16 01:33:13 2010
EcryptfsInUse: Yes
InstallationMedia: Ubuntu 10.04.1 LTS "Lucid Lynx" - Release amd64 (20100816.1)
PackageArchitecture: all
ProcEnviron:
 LANG=fr_FR.utf8
 SHELL=/bin/bash
SourcePackage: jokosher