Incosistent redstone block - Powering piston but not a redstone lamp or redstone dust

This bug is related to MC-108

The redstone block powers the sticky piston (facing up) below it, it also powers pistons beside it but does not give a redstone output.

In picture 2013-02-01_15.37.24.png it shows the redstone block powering the piston below and activating the pistons beside

In picture 2013-02-01_15.39.06.png it shows no redstone output is given out as the redstone lamp is not lit

In picture 2013-02-01_15.50.21.png it shows no redstone output is given.

To recreate:
1.Place a sticky piston with its sticky side facing up 2 blocks above the ground
2.Place a redstone block above it
3. Place piston to the left of the sticky piston (with the redstone block above it) this piston should extend.
4. Place a redstone lamp beside the piston (with the redstone block above it) notice it doesn't light up
5. Place 2 blocks beside the piston (with the redstone block above it) then place redstone dust, notice the redstone does not light up. shown in picture 2013-02-01_15.50.21.png