O2 online WAP settings (always online for newer GPRS handsets):
Note: Different settings for contract and PAYG (Pay as you go)

Homepage: http://wap.o2.co.uk/
APN address (contract): wap.o2.co.uk
APN address (PAYG): payandgo.o2.co.uk
Gateway (IP) address : 193.113.200.195
Username : o2wap (contract) / payandgo (PAYG)
Password: password
Session type: Continuous / permanent
Port number: 9201
Authentication: Normal

O2 online MMS Settings: (GPRS and MMS handsets only)
Note: Different settings for contract and PAYG (Pay as you go)

Access point name: wap.o2.co.uk (contract customers) or payandgo.o2.co.uk (pay-as-you-go customers)
Username: o2wap (contract customers) or payandgo (pay-as-you-go customers)
Password: password
Authentication: Normal
Data bearer: GPRS
Gateway IP address: 193.113.200.195
Session mode: Permanent
URL address: http://mmsc.mms.o2.co.uk:8002