This morning while logged on inside the webmin interface, I saw that there were 10 packages to update. Without much thought, I just hit the “update packages” button and it went on its merry way. Unfortunately, the consequence was not very merry for me and my server, as when the updates were completed Apache would not start, complaining of a problem with mod-apache2-lib-php5.
After much searching and talking to my friend Google, I found that the problem was caused by what is probably a bug with the way Webmin applies the updates. For some reason, the update process removed mod-apache2-lib-php5 so that it became disabled. If you enable the module, you will encounter the same error that I did. The way to fix this module is to reinstall it using aptitude install command such as outlined here
Next time, I will just fire up the shell and do it the old fashioned way.