[Mailman-Users] Unsure what to do with web page "Bug in Mailman version 2.1.20"

[Teijo]

Hello,

After updating from Ubuntu 12.04 to 14.04 (Apache 2.2 to 2.4), only page 
content I seem to get is "Bug in Mailman version 2.1.20". No matter if I 
navigate to my Mailman's main page or to the given list's page.

One problem is that there seems to be nothing useful in error log, 
although I set loglevel to debug.

I have chrooted Apache some years ago, and it's still chrooted.

I have not noticed any other problems with Mailman after server update.

Best,

Teijo