The UK 3G providers have draconian filters on phones and modems. It's ostensibly to stop kids looking at porn and other 'harmful content'. All kinds of sites are blocked; they even had Wikipedia blocked for a while over some bullshit. I think you can get the block lifted by sending in a copy of your ID to prove you are over 18.
"A flower can not remain in bloom for years, but a garden can be cultivated to bloom throughout seasons and years." - xsplat