Block 156325 was generated after 156326?

[windywinter]

Block 156325

Short link: http://blockexplorer.com/b/156325
Hash?: 0000000000000d5e839cee6bb9e079b3c41dd0605abeb3f8d8b7aa5f1692405e
Previous block?: 0000000000000ceb988799c87826dae6167cdfcbee905ea4fbf29bbb63e4d134
Next block?: 00000000000009058e2de991404889e22dfde999b8c7de04a56945e166565aaf
Time?: 2011-12-06 13:54:18

Block 156326?

Short link: http://blockexplorer.com/b/156326
Hash?: 00000000000009058e2de991404889e22dfde999b8c7de04a56945e166565aaf
Previous block?: 0000000000000d5e839cee6bb9e079b3c41dd0605abeb3f8d8b7aa5f1692405e
Time?: 2011-12-06 13:50:51

Is this normal? Or just something went wrong with blockexplorer?

[realnowhereman]

A miner has their clock wrong; there is no way to fake that previous block hash.

Code:

156325: d5e839cee timestamp 1323179658
156326: 9058e2de9 timestamp 1323179451

Nasty.

I suspect that long running nodes can have their time drift from the network, because the offset-from-local is only calculated once.  If the local time then drifts, it doesn't matter that the network average would be able to fix it, because the offset is never looked at (I think; happy to be wrong).

[dree12]

Completely normal. You can generate a block 2 hours in the past and it would be accepted, as long as it isn't after the network median.