After playing fine on my new set up server with a fresh world for more than 3 hours, i just crashed while collecting Sticky Resin with the Wooden Treetap.
Edit: Forgot that at 00:00 my dedicated server is configured for automatic restart. So i guess MC crashed instead of showing a connection loss?
Crash Log (starting at the time where the first error occured):
Display Spoiler
2012-09-16 23:49:34 [INFO] [STDOUT] setupTexture: "/ic2/sprites/GUIGenerator.png", id: 257
2012-09-16 23:49:57 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:49:57 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:50:40 [INFO] [STDOUT] setupTexture: "/ic2/sprites/GUIElectricBlock.png", id: 258
2012-09-16 23:52:05 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:52:05 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:56:27 [INFO] [STDOUT] setupTexture: "/ic2/sprites/GUIMacerator.png", id: 259
2012-09-16 23:56:49 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:56:49 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:57:09 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:57:09 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:57:29 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:57:29 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:57:32 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:57:32 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:57:49 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:57:49 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:58:09 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:58:09 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:58:29 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:58:29 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:58:49 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:58:49 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:59:09 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:59:09 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:59:29 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:59:29 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-16 23:59:38 [INFO] [STDOUT] Error in class 'SourceLWJGL OpenAL'
2012-09-16 23:59:38 [INFO] [STDOUT] Channel null in method 'stop'
2012-09-17 00:00:06 [INFO] [STDERR] java.lang.NullPointerException
2012-09-17 00:00:06 [INFO] [STDERR] at ic2.common.NetworkManagerClient.initiateKeyUpdate(NetworkManagerClient.java:117)
2012-09-17 00:00:06 [INFO] [STDERR] at ic2.common.KeyboardClient.sendKeyUpdate(KeyboardClient.java:47)
2012-09-17 00:00:06 [INFO] [STDERR] at ic2.common.PlatformClient.tickStart(PlatformClient.java:437)
2012-09-17 00:00:06 [INFO] [STDERR] at cpw.mods.fml.common.SingleIntervalHandler.tickStart(SingleIntervalHandler.java:16)
2012-09-17 00:00:06 [INFO] [STDERR] at cpw.mods.fml.common.FMLCommonHandler.tickStart(FMLCommonHandler.java:107)
2012-09-17 00:00:06 [INFO] [STDERR] at cpw.mods.fml.common.FMLCommonHandler.onPreClientTick(FMLCommonHandler.java:363)
2012-09-17 00:00:06 [INFO] [STDERR] at net.minecraft.client.Minecraft.l(Minecraft.java:1432)
2012-09-17 00:00:06 [INFO] [STDERR] at net.minecraft.client.Minecraft.J(Minecraft.java:834)
2012-09-17 00:00:06 [INFO] [STDERR] at net.minecraft.client.Minecraft.run(Minecraft.java:764)
2012-09-17 00:00:06 [INFO] [STDERR] at java.lang.Thread.run(Unknown Source)
2012-09-17 00:00:16 [INFO] [STDOUT] Stopping!
2012-09-17 00:00:16 [INFO] [STDOUT] SoundSystem shutting down...
2012-09-17 00:00:16 [INFO] [STDOUT] Author: Paul Lamb, www.paulscode.com2012-09-17 00:00:50 [INFO] [STDERR] Someone is closing me!