[Seaside] [Glass] Why session locking is necessary for Seaside?

[Johan Brichau]

>> I am intrigued about the ORIGINAL needs of such a need. Because as Pharo and GemStone and too it makes me wonder if the lock would be needed on GemStone.
> I've read some of the newer Seaside code and while I can easily tell that there is still session state being copied and restored (see senders and implementers of snapShotCopy and restoreFromSnapShot:), it is not easy to tell how it is being protected from logical or physical corruption ... WACache has a mutex protecting the cache updates, but I still don't see how the component snapshots are being protected from concurrent updates ... 

That should be the WAMutualExclusionFilter, no?
This one is never installed in the Gemstone code.

cheers
Johan