same problem here with an O2 sim card. Previously with iPhone and BT Openzone login was automatic. Now with N900, having changed tariff from iPhone to reg "smart phone" tarrif, have to login manually by selecting O2 from partner login dropdown then entering phone number.

Error message is "cannot complete logon call". O2 baffled. Tried all sorts of resets. No joy.

Same prob with The Cloud hotspots. Error message is different though. First it was simple "login error" but now, since MAC address reset by O2, error is "You cannot add another device to your account"

wifi fine at home and elsewhere (including starbucks 'Bell hotspot' in the US which requires a login). it's just the UK "unlimited wifi" hotspots from BT and The Cloud causing the prob.

Just to be clear, I see no evidence of a Java applet on the login pages. It's all javascript in the browser. My laptop gets the same error message from The Cloud using firefox and chrome (which you'd expect cos the laptop isn't auth to use the wifi via O2 login and doesn't have a sim card - but the N900 is and does).

Possibilities:

security feature in Maemo/browser preventing sending of MAC address during login?

MAC address sent but somehow on a list of not-authed devices (ie not a smartphone)?

some other (javascript?) interrogation of device to establish presence of authed sim card is failing?

Anyone solved this and actually logged on to a BT Openzone or The Cloud hotspot in the UK on an N900 with any operator's sim card?

Rich