silverstripe/silverstripe-framework — pull request #2968 by tylerkidd (2014-03-19 18:30:26+00:00)
Title: doRollback was setting new version number on draft

This is problematic for DataObjects with Versioning enabled. When you roll back, your draft gets a NEW version number, so while the data remains in sync with Live, your version number is ahead of the most recently published version that is Live.