[MC-1018] Black Lighting under overhangs

System specs:


Hardware Overview:

  Model Name:	iMac
  Model Identifier:	iMac11,3
  Processor Name:	Intel Core i3
  Processor Speed:	3.2 GHz
  Number Of Processors:	1
  Total Number Of Cores:	2
  L2 Cache (per core):	256 KB
  L3 Cache:	4 MB
  Memory:	4 GB
  Processor Interconnect Speed:	5.86 GT/s
  Boot ROM Version:	IM112.0057.B00
  SMC Version (system):	1.59f2
  Serial Number (system):	W80373YQDB6
  Hardware UUID:	A241B705-1FEE-5956-9C12-E5AC61D85161




ATI Radeon HD 5670:

  Chipset Model:	ATI Radeon HD 5670
  Type:	GPU
  Bus:	PCIe
  PCIe Lane Width:	x16
  VRAM (Total):	512 MB
  Vendor:	ATI (0x1002)
  Device ID:	0x68c0
  Revision ID:	0x0000
  ROM Revision:	113-B9850K-133
  EFI Driver Version:	01.00.416
  Displays:
iMac:
  Resolution:	2560 x 1440
  Pixel Depth:	32-Bit Color (ARGB8888)
  Main Display:	Yes
  Mirror:	Off
  Online:	Yes
  Built-In:	Yes
  Connection Type:	DisplayPort
Display Connector:
  Status:	No Display Connected




Memory Slots:

  ECC:	Disabled

BANK 0/DIMM0:

  Size:	2 GB
  Type:	DDR3
  Speed:	1333 MHz
  Status:	OK
  Manufacturer:	0x80CE
  Part Number:	0x4D34373142353637334648302D4348392020
  Serial Number:	0x96ED1093

BANK 1/DIMM0:

  Size:	2 GB
  Type:	DDR3
  Speed:	1333 MHz
  Status:	OK
  Manufacturer:	0x80CE
  Part Number:	0x4D34373142353637334648302D4348392020
  Serial Number:	0x96ED1099

BANK 0/DIMM1:

  Size:	Empty
  Type:	Empty
  Speed:	Empty
  Status:	Empty
  Manufacturer:	Empty
  Part Number:	Empty
  Serial Number:	Empty

BANK 1/DIMM1:

  Size:	Empty
  Type:	Empty
  Speed:	Empty
  Status:	Empty
  Manufacturer:	Empty
  Part Number:	Empty
  Serial Number:	Empty

Latest Java
Mac OSX 10.6.8

Sometimes terrain is pitch black.

The only way I have found to reproduce this is:

1. Generating new terrain
2. Re-rendering new terrian

I have never seen this happen on horizontal surfaces, but it happens all the time on the sides of mountains. The only way to fix it is to destroy some blocks that are effected, and the rest in the area will sometimes fix themselves. Sometimes all I have to do is walk into the dark are and it will fix.