I know this post is old, but here is how I got CIFS working.
-With Angstrom booted on eMMC I put mSD card with Robert Nelson's Ubuntu image on it into mmc slot.
mkdir /mnt/sd1
mkdir /mnt/sd2
mount /dev/mmcblk1p1 /mnt/sd1
mount /dev/mmcblk1p2 /mnt/sd2
cd /mnt/sd1
mkimage -A arm -O linux -T kernel -C none -a 0x80008000 -e 0x80008000
-n kernel -d ./zImage ./uImage
cp uImage /boot
cp -r /mnt/sd2/lib/modules /lib/
depmod -a
Now I can mount folders on my Windows network with:
mount -t cifs -o username="username",password="
password" //server/share /mnt/directory