you can mount //server/share, but not //server/share/path
the syntax is:
where "sharename" is the name you give to the top level share on your NAS.
so, if you have a share called media, with three subfolders (music, movies, and photos for example), you will have to mount media and then browse to music, movies, or photos. if you want a separate mount for each of these, you'll have to create a share for each of them on your nas, so you can mount directly like so:
the only other way i can think of to do this would be like so:
sudo mount -t smbfs //192.168.0.102/music /mnt/music -o rw
sudo mount -t smbfs //192.168.0.102/movies /mnt/music -o rw
sudo mount -t smbfs //192.168.0.102/photos /mnt/music -o rw
if you take a look at the second link in my sig, you will find directions on how to enable name resolution for your Mythbuntu box, as well as lots more information on how to mount your nas device.
sudo mount -t smbfs //192.168.0.102/media /tmp/media -o rw
sudo mount /tmp/media/music /mnt/music
sudo mount /tmp/media/movies /mnt/movies
sudo mount /tmp/media/photos /mnt/photos