You can do it...Its hard, technically challenging(I work in IT and I gave up on it -> on my AT&T bb). Unless you have tmobile ..which seems to enabled it out of the box at least stateside via the desktop manager.
My advice...by a PCMIA card or usb wifi dongle. You are talking 10-20 USD versus a huge headache unless you are more of a guru then me/quite a few of us.
Love the 9000!! It's everything I wanted (minus enough ON BOARD memory)!!
<-9700 ---! more memory! small screen&keypad :( ->