According to the archived mail, here are the 3 rules to enforce.
1) All text must be UTF-8
2) Lines are limited to 72 characters; longer lines must be continued
3) Sections are divided by blank lines
To my knowledge, 2 has been fixed some months ago. There are still some people having issues in maven but I believe they use older plexus-archiver versions.
As for 1 and 3, I am not sure. These definitively need to be looked into.