Incorrect IPTables default rules file

I'm not fully certain if this applies to Virtualmin, or Webmin, or possibly to the VMin installation script.

But in a fresh VMin installation with current version, where I just started fiddling a bit with IPTables, I think an incorrect default config was created. My assumption is that it was done by VMin, since there exist rules for ports 10000, 20000, imap, pop3 etc.

The problem as I understand it: In /etc/iptables.up.rules, in the "filter" section, the following lines are missing:

*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]

Instead, the file generated starts like this:

# Generated by webmin
*filter
-A INPUT -p udp -m udp --dport domain -j ACCEPT
-A INPUT -p tcp -m tcp --dport 20000 -j ACCEPT
-A INPUT -p tcp -m tcp --dport 10000 -j ACCEPT
...

The missing lines are, as far as I see it, required so that the Webmin module recognizes those default chains, and displays the "Set default action to:" buttons. Without those lines, the INPUT rules do not appear at all in Webmin, as if the "filter" table was completely empty and did not even have default policies.

When I manually "add" a chain named INPUT, the line in the config file reads :INPUT - [0:0], causing the "Set default action to:" button to be missing.