The 1.8 version of the famous mod rocket arena for quake 3 is not done yet. But, until it will be, we will be able to test the beta maps.
The website chaosbunnies.de has released a pack with the maps and scripts which allow you to switch between the map versions.
To install the mappack, download and extract it on your quake 3 directory
If you want to join a server with the new beta maps, execute the mappack-beta script (.bat on windows; .sh on linux).
If you want to join a server with the classic maps (the 1.76 ones), execute the mappack-normal script (.bat on windows; .sh on linux).
The scripts just rename the maps.
Here, some servers with the new mappack:

85.25.150.195:27962 #chaos.crew

88.191.76.125:27960 Clan-M.

88.191.76.125:27962 RA3Pickup.fr

85.25.150.195:27962 #chaos.crew
If you provide other mirrors or other servers with the mappack, write me an iMsg or write it on the comments.