offline update

1.Install bash_3.2-5_i386.deb
  #dpkg -i bash_3.2-5_i386.deb



online update

1.Edit the sources.list
  #vi /etc/apt/sources.list

2.Add moxa debian server 
  deb http://debian.moxa.com/debian/ lenny main

3.Add moxa debian server public key and update the list
  #apt-key add NEW-MOXA-SYS-DEBIAN-KEY
  #apt-get update

4.Install the new version bash package
  #apt-get install bash