Node versionable = parent.addNode("versionable", "nt:myversionable");
versionable.setProperty("foo", "A");
parent.save();
VersionHistory history = versionable.getVersionHistory();
Version versionA = versionable.checkin();
history.addVersionLabel(versionA.getName(), "labelA", false);
versionable.checkout();
versionable.setProperty("foo", "B");
parent.save();
Version versionB = versionable.checkin();