Bungee Cord servers sharing inventories

I'm currently setting up my servers, I have three servers linked including the Lobby. I want to share inventories across all the servers.

My servers are running FTB Infinity 1.3.4 (minecraft version 1.7.10) with cauldron installed.

I've tried "InventorySQL" and "playerSQL" but neither of them work with my servers. Are there any alternatives to this?

Thanks, George.