Sharing a ntfs partition using Samba

I have a Windows/Linux box, I run Linux and I mount the windows ntfs
partition, so that all the Linux users in that machine can access that
partition. Then I want to share this ntfs partition in the network
using samba.

I can see the partition from the samba clients but I can not access
it. I guess it's a permission problem, but I am not sure. Let's say I
have in that machine (the Windows/Linux one) a user called user1 that
can use the partition from the local machine, and in all the other
machines I have the same user, and I have added that user to the samba
server as well. But from windows machine, using the same user, I can
not access the share (is asking the username and password all the
time), and from another Linux machien using samba I get the following:

smbclient //DANIEL/DaniWindows -U user1
Password:
Domain=[DANIEL] OS=[Unix] Server=[Samba 3.0.9-1.fc3]
tree connect failed: NT_STATUS_BAD_NETWORK_NAME

But I can access the other shares, the ones that are not ntfs.

This is the line in /etc/fstab that mounts the windows partition I
want to access:
/dev/hda1 /mnt/windows ntfs
uid=500,gid=500,umask=555,ro,owner,user

Should I need to add sth to make the share available through samba ?

Thanks !