помогите плиз с майном

поиграю 5 мин начинает лагать и вылетает
Minecraft has stopped running because it encountered a problem; Exception while updating neighbours

A full error report has been saved to C:\Documents and Settings\Администратор\Application Data\.minecraft\crash-reports\crash-2012-11-22_18.10.13-server.txt - Please include a copy of that file (Not this screen!) if you report this crash to anyone; without it, they will not be able to help fix the crash

--- BEGIN ERROR REPORT e292d6c7 --------
Full report at:
C:\Documents and Settings\Администратор\Application Data\.minecraft\crash-reports\crash-2012-11-22_18.10.13-server.txt
Please show that file to Mojang, NOT just this screen!

Generated 22.11.12 18:10

-- Head --
Stacktrace:
at java.lang.ClassLoader.findLoadedClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)

-- Block being updated --
Details:
Source block type: ID #0
Block type: ID #78 (tile.snow // amp)
Block data value: 0 / 0x0 / 0b0000
Block location: World: (639,4,198), Chunk: (at 15,0,6 in 39,12; contains blocks 624,0,192 to 639,255,207), Region: (1,0; contains chunks 32,0 to 63,31, blocks 512,0,0 to 1023,255,511)
Stacktrace:
на версии 1.4.7 таково небыло
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