How to setup PPTP manually?

[Zoltan Boszormenyi]

Hi,

I need to configure a VPN connection to a PPTP server
without NetworkManager.

The reason: I had to configure my network in a way so there's
a bridge interface so a KVM/QEMU guest can get its IP address
via DHCP from my router and this way VNC can be NAT-ed
from the router to go directly to the KVM guest.

The ethernet and bridge interfaces are now outside of the
NetworkManager realm (NM_CONTROLLED=no in ifcfg-* files)
and the PPTP VPN configured by NetworkManager is greyed out
and cannot be started.

Can someone help me with manual PPTP configuration?

Thanks in advance,
Zoltán Böszörményi