There seems to be rash of these Activation Required errors and seem to be affecting, mostly, iPad 2 models.
I have an iPad 2, but currently, it is unaffected by this issue.
It, also, seems this Activation Server Required error is affecting some other older iDevices, as well.
So, clearly, this bug/glitch/error/issue hasn't affected every single older iDevice still in existence and still running.
Hopefully, Apple is aware of this issue.
This could be just a computer/server glitch/issue.
Computers CAN have issues.
No one, maybe not even Apple, may be aware of what is really going on!
This issue seems to have all started over this weekend.
OR
Apple is doing some work on their servers that maybe leaving them temporarily down and unavailable/inaccessible.
Perhaps preparing some stuff for this coming Tuesday's special event, maybe?
No one, but Apple may know what is going on.
Just to make sure they are aware, make Apple aware and submit feedback here.
iPad Feedback
http://www.apple.com/feedback/ipad.html
Good Luck!