And bitcoin#5770

We have to include this into the 0.11.2 release notes:

Mining and relay policy enhancements

Darkcoin Core's block templates are now for version 3 blocks only, and any mining software relying on its getblocktemplate must be updated in parallel to use libblkmaker either version 0.4.2 or any version from 0.5.1 onward. If you are solo mining, this will affect you the moment you upgrade Darkcoin Core, which must be done prior to BIP66 achieving its 951/1001 status. If you are mining with the stratum mining protocol: this does not affect you. If you are mining with the getblocktemplate protocol to a pool: this will affect you at the pool operator's discretion, which must be no later than BIP66 achieving its 951/1001 status.

BIP 66: strict DER encoding for signatures

Darkcoin Core 0.11.2 implements BIP 66, which introduces block version 3, and a new consensus rule, which prohibits non-DER signatures. Such transactions have been non-standard since Darkcoin 0.8, but were technically still permitted inside blocks.
This change breaks the dependency on OpenSSL's signature parsing, and is required if implementations would want to remove all of OpenSSL from the consensus code.
The same miner-voting mechanism as in BIP 34 is used: when 751 out of a sequence of 1001 blocks have version number 3 or higher, the new consensus rule becomes active for those blocks. When 951 out of a sequence of 1001 blocks have version number 3 or higher, it becomes mandatory for all blocks.
Backward compatibility with current mining software is NOT provided, thus miners should read the first paragraph of "Mining and relay policy enhancements" above.

Also compare with upstream release notes: https://github.com/bitcoin/bitcoin/blob/0.10/doc/release-notes.md#mining-and-relay-policy-enhancements
More info on BIP 66: https://github.com/bitcoin/bips/blob/master/bip-0066.mediawiki