ORA-27054 from NFS mounted filesystem

Recently I was running a RMAN restore from a NFS mounted filesystem (/d06) on a Sun Solaris server and hitting the following error --

channel t3: reading from backup piece /d06/BACKUP/PWTEST/FULL0_0djgp08h_1_1.19May2008.1151
ORA-19870: error reading backup piece /d06/BACKUP/PWTEST/FULL0_0cjgovuv_1_1.19May2008.1151
ORA-19505: failed to identify file "/d06/BACKUP/PWTEST/FULL0_0cjgovuv_1_1.19May2008.1151"
ORA-27054: NFS file system where the file is created or resides is not mounted with correct options

Additional information: 2
channel t4: starting datafile backupset restore
channel t4: specifying datafile(s) to restore from backup set
restoring datafile 00002 to +PWTESTRP_DATA
restoring datafile 00010 to +PWTESTRP_DATA
channel t4: reading from backup piece /d06/BACKUP/PWTEST/FULL0_0ejgp0ho_1_1.19May2008.1151
channel t1: starting datafile backupset restore
channel t1: specifying datafile(s) to restore from backup set

Remounting the filesystem with the correct options fixed the issue -
# umount /d06
# mount -o rw,bg,hard,nointr,rsize=32768,wsize=32768,tcp,vers=3,timeo=600,actimeo=0 db01-pwprd.ctn:/d06 /d06