Last modified: 2012-04-29 17:42:17 UTC
action=history does not show the revision length of RevDel revision, but Special:Undelete does. That looks wrong. Please check the RevDel bitfield also for the revision length on Special:Undelete Thanks.
Maybe it is easy to make the revision length public on action=history, because prop=revisions output it already. Special:Recentchanges also give the byte difference. Change bug summary.
Already fixed with r111251