Samba Errors (CIFS VFS: Write2 ret -11 or ret -28) RHEL 5

I have been getting the following types of errors across a lot of servers for some time:

messages-20131122:Nov 22 01:25:59 Server1 kernel: CIFS VFS: Write2 ret -11, wrote 0
messages-20131122-Nov 22 01:26:00 Server2 kernel: CIFS VFS: No response to cmd 47 mid 59156
messages-20131122:Nov 22 01:26:00 Server2 kernel: CIFS VFS: Write2 ret -11, wrote 0
messages-20131122-Nov 22 01:26:00 Server1 kernel: CIFS VFS: No response to cmd 47 mid 51207
messages-20131122:Nov 22 01:26:00 Server1 kernel: CIFS VFS: Write2 ret -11, wrote 0

I have already tied the suggestion

https://access.redhat.com/site/solutions/62912

It didnt help. I have also found references to

echo 0 > /proc/fs/cifs/OplockEnabled

I have also tried this without success. These occur quite regularly and over a standard weekend I end up with some 12,000 related messages over a few hundred servers.

Previously we were running Samba 3.0.xx but have recently upgraded to samba 3X to deal with a problem in winbind/AD. Sample rpm list is below. If more information is required I will provide what I can

pam_smb-1.1.7-7.2.1
pam_smb-1.1.7-7.2.1
libsmbclient-3.0.33-3.29.el5_6.2
samba3x-3.6.6-0.136.el5
samba3x-winbind-3.6.6-0.136.el5
samba3x-client-3.6.6-0.136.el5
samba3x-common-3.6.6-0.136.el5