Every time the server that I run re-starts (or Im pretty sure thats it, it may be unloading and reloading chunks), all iron tanks are broken and I have to break and re place a block to fix it along with all of my players. The auto liquid refilling works though, so it is more of an annoyance then anything. Server runs the latest railcraft release and the latest MCPC+ off of jenkins as of yesterday. Uses the Mining Dead modpack, custom built for our 3 servers. Find it on page 2 of technicpack.net and if I see you on I can show you the issue.

I've never heard of such issues on anything other than MCPC+

Okay, so in that case you don't have to fix it as its not technically your problem. Although it would be great for you to fix it on your part anyhow, for all of our sakes and compatibility, and if people would like the mod better if that wasnt an issue.

The only thing I can think of is that MCPC+ implements world.blockExists() wrong.