To create a PvP region in a non-PvP server, do the following steps.

1. Install WorldEdit and WorldGuard, see our How to install a Bukkit plugin on how to do that.
2. Using WinSCP or FileZilla, log into your server and open the server.properties file. Set PVP to true, restart the server.
3. Now type the command: /region flag __global__ pvp deny . That'll set the whole world as a no-PVP region.
4. Now using the WorldEdit //wand, define a new region for your desired PvP area, see our Protecting a area of land page on how to create a region.
5. After you've created the new region area, you'll want to enable the PVP flag for that region. type: /region flag pvp allow
6. Now we need to set our PvP region to have a higher priority (1) then our global region (0), we do that by typing: /region priority 1

You should now have a area of land with PvP enabled in a world with PvP disabled. If you need assistance installing WorldEdit/WorldGuard or setting up a PvP region, Send us a ticket and we'll help you out.

Troubleshooting

Some plugins like MultiVerse can interfere with PvP interaction. If you believe you've followed the steps correctly and PvP isn't working, try disabling all plugins except WorldEdit & WorldGuard and see if it works. If it does then another plugin is interfering with PvP