[Samba] Speed problem connecting to samba over Internet

[James Lewis]

I have a samba file share configured on RH7.3. smb.conf is below.
 
I have a stunnel running with:  stunnel -d 2222 -r localhost:139
 
I'm connecting to this from Windows using instructions as per here:
http://www.cheswick.com/ches/cheap/tunnelsolution.html , which is
basically stunnel running in Windows stunnelling port 139 on a local IP
to 2222 on my remote server, so that I can access the share via (in
windows speak) \\localIP\test 
 
It all works fine, but it takes a loooong time to make connections. Once
a connection is established, the speed is fine - a single 12Mb file
takes about 90 seconds to transfer from the server. Through windows
explorer, ten 1k files take about 15 seconds to transfer (pretty slow).
Through a Windows text editor though, a single 1k text file takes about
8 seconds to open, and about 10 seconds to save - operations that would
both be instantaneous on the local disk.
 
TIA for any tips/advice. 
 
(I can't connect directly to the server because my ISP has port 139
blocked)
 
James
 
smb.conf:
 
[global]
        workgroup = S1
        encrypt passwords = yes
[test]
        comment = test
        path = /some/path/to/some/webspace
        read only = no
        guest ok = no