Yes, it seems to happen when there is a slight lag at the moment the door is opened. The server registers that the door is open, but the client does not. If you walk forward, the client "predicts" that it will obstruct you, and makes it look like you ran into the door, and then a moment later, the server reports your actual position as being on the other side of the door, and you "morph through it", as you put it.
So this has been happening a few times lately, when I would come up to a gate such as in the caves or in a building that has a bay door that needs to open, I would try and click on it and it wouldn't move or open. So, as I move forward towards the door, I morph through it magically as if I opened it as I reappear on the other side of the door. This doesn't happen a lot but since the last issue release, it seems it has been happening much more. Anyone else out there experience this?