Maping a drive not working with ip-address only with servername

Hi,

i am connectet with VPN to a Windows 2003 Server (my computer is not in the
domain)

All workes fine but i cannot access the shares on the server like this:

\\10.0.1.1\share (share not working ping is ok)

\\servername\share (share not working ping for the sever name is not working
but i can resolve this with dns-suffix or hosts table)

\\servername.net.domain.com\share (works fine)

I need this connect with ip-adress because some applications with click-once
deployment are configured with ip-adresses.

The same computer with XP booting, all is working fine for years

Any ideas

--
Bernd from Germany