This "bug" is extremely old. What I don't understand is that I thought something was done to fix it long ago, because the rash of Jeep-inside-your-tank-killing-you stopped long ago and only restarted recently. If it wasn't fixed, why did it stop? Did everyone just decide to be good boys? Did they just forget the exploit? Or did HTC remove the fix (which I vaguely recall involved rounds not being effective until they traveled a certain distance, leading to a different "bug" of point blank shots being ineffective)?
By the way, it is possible, depending on your position, to be unable to defend against this: if you are in town near a corner the Jeep can turn in behind you and be close enough that you can't depress the main gun (or therefore the coax) to hit them. This is relevant, of course, only the the tanks without AA like the T34s, and the HE trick probably still works.