Help Please in Setting up VPN On Fido iphone 4 , works on wifi and Not 3G ?? Paid $5

[absorber1]

what i would like to to do is connect to my UK VPN PPTP account using 3G , works great on wifi . But get error pptp - vpn server dit not respond when i try on 3G . Called Fido(canada) and asked if they where blocking , they said NO , but have to add vpn to my account for $5 , said ok paid $5 and it still does not work !!! they said they dont support VPN on iphone and there maybe other settings to change and have to talk to my IT guy ???

Any Help would be great , Cheers ,

Running 4.01 Jailbroken, factory unlocked.