Our favorite WFS-T server complement of UMN Mapserver is TinyOWS. We like the simplicity of it so much, that we packaged it for Ubuntu and added it to OSGeoLive. Installation is easy:
sudo add-apt-repository ppa:ubuntugis/ubuntugis-unstable
sudo apt-get update
sudo apt-get install tinyows
The simplicity is a little bit too much, when it comes to serve multiple WFS-T on the same server. There is only one configuration file, but we want a configuration for each service. There are solutions for that, but I never saw a documentation of the most elegant solution we found. It uses Apache rewrite capabilities to set the TINYOWS_CONFIG_FILE environment variable according to the called URL:
# URL rewriting
RewriteEngine On
# Forbid direct access
RewriteRule ^/cgi-bin/.*$ - [F]
# Rewrite /xxx to /cgi-bin/tinyows with TINYOWS_CONFIG_FILE=/etc/tinyows/xxx.xml
RewriteRule ^/(.+)$ /cgi-bin/tinyows [QSA,PT,L,E=TINYOWS_CONFIG_FILE:/etc/tinyows/$1.xml]
This configuration included in a virtual host declaration (wfs.example.com) serves your WFS-T on wfs.example.com/servicename.