You can't fool me. You're trying to start somethin! I just know it!
I guess it depends on whether you think the Son not knowing something makes Him unequal. I could see why you think so.
Another angle to consider is that Christ said that while on earth, in an earthly body. That is, He had chosen to limit Himself, or to lay aside certain prerogatives enjoyed by a spiritual, divine being. Perhaps when He said that He didn't know, He meant that He had left that knowledge behind in the heavenly realms.
Or, if He could choose to limit Himself while on earth, He can also limit Himself for all of human history. Perhaps, for some reason we may not be able to discern, He chooses not to know the date and time of His return until the Father says it's go time.
Or, if you want to jump a bit further down the rabbit-hole, consider this. The Son is an eternal, uncreated being who chooses to enter the limitations of a temporal existence. Perhaps this temporal limitation is still with Him, as a resurrected man, and will not be lifted until the end of time (the Second Coming, the Last Judgment, whatever).