Cant access "private" SMB/CIFS shares from Linux

So I have a ReadyNas Duo with several shares some public, some restricted from some groups and users.
It was working for months,but since last Monday I cant access any more from the Linux systems (excepts for the public/guest shares)

I cant access browsing network from dolphin or nautilus, my entries in fstab no longer work, and cant mount them manually ...
The shares work fine from XP, 2000,2003 or 7

But from any Linux distro I tried ...

mount -t cifs -o username=???,password=???,domain=??? //nas-ip/shared /mnt/shaerd
mount error(11): Resource temporarily unavailable
Refer to the mount.cifs(8) manual page (e.g. man mount.cifs)

that worked last week but not today ... (if I use a wrong password the error is Permission denied so it let me login ... )
Also I don't have any problem accessing shares in other pc's from Linux
If I browse the network (using any Linux file explorer) I can view the nas shaers and I can enter any public one,
but when I tried a shared that requires user it refuses (I'm sure I'm using the right password and also tried creating new users)

I found this (which seems to be my same problem)
http://ubuntuforums.org/showthread.php?t=1506377

But restarting samba daemon didn't work for me ...