Sadly I can say this is true for at least two US carriers. One had obfuscated the number by padding it in a unique identifier header, and the other would send

Sadly I can say this is true for at least two US carriers. One had obfuscated the number by padding it in a unique identifier header, and the other would send it along in some cases (i can't remember if it was on a partner by partner basis). Also, almost every HTTP request on a mobile phone still passes through a HTTP Proxy. Generally, so avoiding opera, won't do any good. That is what the APN does. What typically will get you off the carriers proxies is to use wi-fi, despite what the author says. They tend to get out of the loop if you're using someone else's network.