Note from reporter: This issue has been re-sent by me due to over four months without response. Thank you for reading. I hope it gets read this time.
This occurs in all current versions of Minecraft. When witches are left idle, and wander around randomly, in the process of them walking, they will ignore the player until they have reached their destination, then attack. This can be severely exploited so that you can kill the witch with no effort at all, or more often confuses players into thinking that the witch is a passive mob. This can be seen in multiple YouTube videos.
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No need to create a second ticket for the same issue.
I just thought something happened with the last one or something, could someone take a look please? Thank you.
I'm honestly confused right now. If anyone is reading this, can anyone tell me why my ticket hasn't been viewed at all by a mod for 7 months now? This is getting very frustrating.

I have read your ticket. What do you expect the mods to do ?
I don't know, give some feedback, test the bug, mark it as confirmed or resolved...
In this video: http://www.youtube.com/watch?v=84hFlHZFqto&feature=c4-overview&list=UUxbMB2KBSV5_a1AWci-mxsA
You can see the witch experiencing this behavior at 25:44. This person was using a few mods at the time, but in no way did it interfere with the witch's AI. I have seen this in vanilla Minecraft videos, as well as experience myself, but couldn't find any at the moment.