[Hampshire] Samba permission problem

I have a strange problem, I have three folders on an ext.USB hard disk which is
formatted to ext3 and I share via Samba for some windows PC's on my network.
Now all the users can see shares and access read and write to them without a
problem. The problem is is that when they save to the samba share the file
permissions comes up as nobody & nogroup

All other files and folders are set to me as the users and group users (the usb
hard disk was recently re formatted from fat32, all the data was backed up and
then restored after the re-format to ext3. How do I stop this permission
problem?

Tim

P.S. Sorry mail admin on previous message I forgot to change default e-mail
transport