hi,

> 	Example where atime is updated when it shouldn't be.
> 	This is similar to when mail is delivered to a mailbox.

i guess it's due to (superfluous?) cache invalidation due to IO_APPEND.

> 	Example where atime is NOT updated when it should be:

it seems like an expected behaviour because the file data is cached locally
and the server will get only non-READ requests like GETATTR which doesn't 
update atime.  i'm not sure why it doesn't occur on 1.5.

YAMAMOTO Takashi