samba - Oct 2007 - smbfs mounts hang when windows machine is rebooted

I am mounting directories from a WinXP SP2 machine to a Debian Linux
2.6.18-4-686 using /etc/fstab of:

 

//winxp/directory /mnt/mountpoint smbfs
username=xxx,password=xxx,uid=xxx,gid=xxx,errors=remount-ro 0 0

 

If I reboot the windows machine, any access to the mountpoint on the linux
box hangs. 

 

umount -f fails due to the device being busy, even though the mount is
inaccessible. umount  -l does work and then I can remount. 

 

I have not had any luck finding any hits when searching for solutions so
that the mounts be timed out and reset automatically. This is a production
app that depends on directories being accessible.

 

Can anyone point me in the right direction?