Hi,
Try this
interface Dialer0
ip address negotiated
ip mtu 1442
ip nat outside
ip virtual-reassembly
encapsulation ppp
dialer pool 1
dialer-group 1
no cdp enable
ppp authentication pap callin
ppp pap sent-username xxxxx password xxxxxxxxxxxxx
crypto map VPNmap
!
ip classless
ip route 0.0.0.0 0.0.0.0 Dialer0