G502 and Secure websites (https)

I have a new Sony Ericsson G502 and am encountering the most bizarre problem.
I am unable to connect to secure websites, that is https:// websites such as gmail using the web browser. The error message I receive is "Communication Failure. Secure connection failed."
This by itself is not the strangest part of course. Using a different sim card I have found that I no longer recieve this error. I am with Vodafone NZ and both of the sims I used were also with this provider. I cannot understand why one sim allows secure connections but the other does not.

If anyone has experienced this issue with another provider or has any ideas on how to resolve this it would be much appreciated.

You could try and check with Vodafone. There may be a service that has to be enabled for that SIM-card, as is the case with picture messages.

i have problem debranding my SE G502.