I am seeing this crash in SMP with your mod installed. It happens when creepers start spawning on the server. It appears to be a specific creeper causing it (no idea which one since it crashes before I can see it) as others will spawn fine up to that point.

http://openeye.openmods.info/crashes/9698277e919fad66d1e15ec411b595e1

You mind getting me a full crash log, I'm not really getting much info from that open eye crash info (Doesn't even mention EC).

http://paste.ubuntu.com/7773001/
Edit from Lomeli: Use a pastebin next time ><

1. Test on a vanilla server first. I (and most modders) don't provide support for MCPC+/Cauldron because it tends to be 3x buggier than Vanilla Forge. If it works on a vanilla server, please report it to MCPC+/Cauldron, not me as it's a problem on their side.
2. What other mods are you using?
3. Have you tried with just EC installed?
4. Disable creeper spawning in the configs and spawn each creeper until one produces a crash so I know which one may be causing a problem.

1. It does happen in forge with a little bit different error.
   http://paste.ubuntu.com/7773334/
2. This is the list of mods.
   http://paste.ubuntu.com/7773338/
3. With just EC installed it "appears" to be ok. Without EC installed it is ok.
4. It is the EU creeper.

Which makes sense, I take it that creeper only spawns with IC2 installed.

Should be fixed with 5e5acc0