But, I found an application, called kvpnc.
# apt-get install kvpnc
But, this is one so loosely tested application.
First of all one can't disconnect once connected to PPTP/VPN server.
Second, if you kill kvpnc, the PPP adapter won't be removed.
Third, by default, it will dial very first profile only, even if you select some other profile.
And so fourth...
Anyone has got some alternative?