One cannot build net-mail/qmailadmin on a system using vpopmail with mysql use flag. I was able to hack the MAKEFILE by addinging '-lmysqlclient'. Not sure how to properly handle this in an ebuild.
Adding a link to the forum discussion on this.
Created attachment 209788 [details] My attempt at an ebuild I tried to add an ebuild that adds a mysql USE flag.
Fixed properly in 1.2.15. Please attach patches in future, not full files.