tcp,retry=X combination of options for NFS mounts not working

Issue

Setting "retry=10" should cause the mount command to retry mounts for 10 minutes. What is observed is that thata little more than 6 minutes on RHEL 5.4, RHEL 5.5, RHEL 5.7, and RHEL 6.1, and we get 42 seconds on RHEL 5.6. This may result into lot of HA fail over events which can manifest themselves as >42 second outages, causing this investigation. The business impact is failed processes (e.g. renderfarm jobs) during what should be a reasonable HA recovery event.

The reproducer is simple. For a test mountpoint of 192.000.00.000:/usr/pic1, perform:

iptables -I OUTPUT 1 -d 192.000.00.000/32 -j DROP
/usr/bin/time /sbin/mount.nfs 192.000.00.000:/usr/pic1 /mnt/tmp -o tcp,retry=10