Old 1.8 Snapshot Worlds Not Loading In 14w28a

When attempting to join a server made on previous snapshots, the game displays the attached screen, and the server console reads:

TranslatableComponent{key='disconnect.genericReason', args=[Internal Exception: java.io.IOException: Broken pipe], siblings=[], style=Style{hasParent=false, color=null, bold=null, italic=null, underlined=null, obfuscated=null, clickEvent=null, hoverEvent=null, insertion=null}}