The extra Gentoo documentation for Mailman could use a little precision. Should take about 2 minutes to change! :)
Right at the top, there are instructions to "add -D MAILMAN to the /etc/conf.d/apache2 file". At first I thought I was supposed to add "-D MAILMAN" all by itself on a single line at the end of the file. The documentation should say something like "add the -D MAILMAN flag to the APACHE2_OPTS variable".
Second, right before the instructions on changing the /etc/mail/aliases, there should be a note for Postfix users to read the last section of the document. I followed the instructions and ended up modifying the file only to find out that I should not have done that. I had already read the installation instructions on Mailman's website before, but I had forgotten that exception when I was actually installing Mailman.
Created attachment 102862 [details, diff]
diff for the README.gentoo file
Here's my take on how it could be phrased.
Also, the dodoc README.gentoo by default creates a .bz2 file, not a .gz file (yes, nitpicking).