How do I use TKL File Server as a VMWare Datastore?

I set up a dedicated server running TKL File Server with 2 x 2TB Sata drives. I want to use this server as a low-cost NAS. 

I've set up samba to sync with users and have been able to connect to the drives in Windows.

My problem is I don't know how to use it as a datastore for my VMWare ESXi4 hosts. I have 2 storage locations already created for guests with RW for 2 users storage and storage2.

/srv/storage on sda1

/home2/storage2 on sdb1

when I df here is what it looks like:

Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/turnkey-root
                      1.8T  1.3G  1.7T   1% /
none                  496M  204K  496M   1% /dev
none                  502M     0  502M   0% /dev/shm
none                  502M  476K  501M   1% /var/run
none                  502M     0  502M   0% /var/lock
none                  502M     0  502M   0% /lib/init/rw
/dev/mapper/groupb-volumeb
                      1.8T  196M  1.7T   1% /home2
/dev/sda2             229M   18M  200M   8% /boot
root@fileserver ~#     

I am using vSphere Client Version 4.0.0 to manage the ESXi hosts

I have been able to connect my 1TB WD World Book this way so I know it can be done.

The ESXi host IP is 10.10.10.20 and the fileserver is 10.10.10.5

Here is the error I receive when I try to connect:

Create NAS datastore
10.10.10.20
Error during the configuration of the host: NFS Error
: Unable to Mount filesystem: Unable to connect to
NFS server
mikebest66
VM002
5/11/2011 9:45:59 AM
5/11/2011 9:46:00 AM
5/11/2011 9:46:31 AM

My guess this is a permissions issue but I don't see how I can give the username and password to fileserver in vSphere when I try to connect the datastore.

Can I allow all IP's in the 10.10.0.0/8 range access on the file server?

Any help would be greatly appreciated.