PennyTel is a VOIP service provider which is similar to Skype. I made it work on my Nokia E72 (S60 V3) Today. It is kindof cool that it allows me to use either my mobile service provider or PennyTel when make calls. PennyTel saves me lots of fortune especially for dialing International calls.
1) You have to register a free account in PennyTel, and buy a plan if want to call landlines or mobiles.
2) In E72, go to Menu – Ctrl. Panel – Settings – Connections – SIP Settings – New SIP Profile
Profile name: PennyTel
Service profile: IETF
Default destination: Internet
Public user name: sip:XXXXXXXX@sip.pennytel.com
User compression: no
Registration: when needed
User security: no
Proxy server: leave it unconfigured
Registrar server
Registrar server address: sip:sip.pennytel.com
Realm: sip.pennytel.com
User name: your username
Password: your password
Tranport type: Auto
Port: 5060
Now go back and check whether Pennytel is registered. It should be 
3) If you have not installed Nokia SIP VOIP on your E72, you need to install Nokia SIP VOIP first before jumping to the next step.
4) Go to Menu – Ctrl. panel – Net sett. – Advanced VoIP settings – VoIP settings, and choose Pennytel.
5) Dial the phone number then choose ‘Net call’ to use PennyTel. Just be aware of that you need to follow the dialing pattern that defined by PennyTel. e.g. 0011 + country code + area code + phone number; 0011 + country code + mobile number
*If you have an Asterisk based PBX server in your office, the VoIP extension also works in the same way. I have tested it too.
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