bitcoin/bitcoin — pull request #2520 by sipa (2013-04-13 22:23:44+00:00)
Title: Require strictly-standard encodings in mempool

This will make the mempool require strictly DER-encoded signatures, and restrict public keys to being either compressed or uncompressed (so no "hybrid" ones).

See the discussion here: http://comments.gmane.org/gmane.comp.bitcoin.devel/1973