All you need is something called MCPC+. Then set it up as a normal vanilla server with the code In text edit
(#!/bin/bash
cd “$(dirname “$0″)”
exec java -Xmx1G -Xms1G -jar [The name of the MCPC+.jar file]). Make it into plain text. Put it all into a folder and run the server. Then install pixelmon like you would by extracting the pixelmonmod.zip and delete the empty mods folder. Drag the data base in the folder and your done.
Message me on skype for more info (Pika-Fu**ing-Chu)
If sombody would like i could take a video of me doing so like a indepth tutorial.
This is for mac the code might change a bit