i'm on ubuntu 12.04.2, kernel 3.2.0-48-generic x86_64, up to date NFSv4, simple exports and accessing them works fine, but this does not work:
file system setup:
/home/user/test					#located on /dev/sda
/home/user/test/Series				#located on /dev/sda has +500 sub directories, e.g.
/home/user/test/Series/24			#located on /dev/sdb used 'mount --bind'
/home/user/test/Series/Star.Trek		#located on /dev/sdc used 'mount --bind' and so forth but also:
/home/user/test/Series/Animation		#located on /dev/sda has +50 sub directories, e.g.
/home/user/test/Series/Animation/Ben10		#located on /dev/sdz used 'mount --bind'

my export file:
/home/funky1/test/       192.168.2.0/24(rw,insecure,fsid=0,nohide,no_root_squash,no_subtree_check,async)
/home/funky1/test/Series       192.168.2.0/24(rw,insecure,nohide,no_root_squash,no_subtree_check,async)
/home/user/test/Series/24       192.168.2.0/24(rw,insecure,nohide,no_root_squash,no_subtree_check,async)
/home/user/test/Series/Star.Trek       192.168.2.0/24(rw,insecure,nohide,no_root_squash,no_subtree_check,async)
/home/user/test/Series/Animation       192.168.2.0/24(rw,insecure,nohide,no_root_squash,no_subtree_check,async)
/home/user/test/Series/Animation/Ben10       192.168.2.0/24(rw,insecure,nohide,no_root_squash,no_subtree_check,async)