This is a suggestion and not a bug report but I feel that (especially in light of the current desync issues) it would be beneficial if the zombies did not aggro a play at login until they move.
I have recently been killed due to logging into a server and being bashed to death by invisible zombies due to the desync problems.
I feel it would be reasonable in normal game play to be able to login to a server and not have the zombie argo you until you move.
This maybe something that will come as they start to modify zombie behavior and bring in the ability for players to sneak more effectively, as mentioned by Rocket in the Rezzed road map discussion.