"/usr/bin/smbmnt" is the /usr/bin/smbmount helper application.

See #man smbmnt
#which smbmnt
#ls -la /usr/bin/smbmnt

smbmnt is probably set as: rwxr-xr-x root root

Use:
#chmod ug+s /usr/bin/smbmnt (to set the suid bits rwsr-s--r-x)

In /etc/fstab add the "suid" option

//Sydog/C /winshare/Sydog_C smbfs noauto,_netdev,user,suid 0 0

Since you are trying to mount SMB shares using the mouse on the desktop icons they might be using the /bin/mount command. In that case set /bin/mount as "r-sr-sr-x root root" (with chmod,chown)

The "user,suid" options also apply to the /dev/fd0 and /dev/cdrom entries in /etc/fstab to allow ordinary users to mount/umount those devices if /bin/mount is set r-sr-sr-x root root.
You need an fstab something like:
//bdfm-rig2/BDFMRIG2_C /mnt/bdfm smbfs noauto,user 0 0
the 'user' bit means any use can mount this mount, the 'noauto' means the mount point is not normally mounted.

You also need to do:
chmod ug+s /usr/bin/smbmnt

This means that smbmnt (called by mount) mount will run as root even if a normal user calls it. Also to unmount a smb share as a normal user you need to use 'smbumount' and again the permissions need changing so it runs as root:
chmod ug+s /usr/bin/smbumount

You also need to create the directory /mnt/bdfm. This needs to be owned by the person wishing to access it. So either (as anybody):

mkdir /mnt/bdfm
[as root] chown pcr20 /mnt/bdfm
or
[as pcr20] mkdir /mnt/bdfm

Once this is done, to mount the file system issue:

mount /mnt/bdfm

and to unmount issue:

smbumount /mnt/bdfm

The files will appear at /mnt/bdfm and will belong to the user who issued the mount command.