0.0.11a was a version of Java Edition Classic released on May 17, 2009, at 11:56 UTC, almost 4 minutes after the release of 0.0.10a to fix the game being unplayable.
While there is a version called "c0.0.11a" in the launcher, it is actually an early development version of 0.0.12a; although labeled "0.0.11a" in-game, it contains files from May 18, 2009 (a day later than the release of this version), and has early multiplayer code present.
This was the first public version of Minecraft, posted on the TIGSource Forum labeled Minecraft (alpha).