Ever since I bought my Samsung BlackJack II smartphone it's had a recurring problem losing its Internet connection. It started within a few days of getting it last Spring. Every couple of days I'd open the mobile browser and instead of my home page I'd see an error message that said "403 Forbidden." There would be no Internet access until the phone was powered off and back on. I did some searching and discovered that others had the same problem. I also found a quicker work-around. By going to the "wireless manager" and turning the phone service off and back on, rather than rebooting the whole phone, I was able to restore the connection much more quickly. But even better, there appears to be an actual fix now.
From the Samsung website BlackJack II owners can download an upgrade to Windows Mobile version WM6.1. In addition to fixing the lost connection "403 Forbidden" problem, there are some other nice improvements to the mobile OS. (Not the least of which is actual Java support so you can now watch youtube videos on the mobile IE browser.)
A couple of warnings. The documentation on installing the upgrade isn't as clear as it could have been. At least once I had to power the phone back on when the instructions didn't say to. And maybe more importantly, after the upgrade I continued to have the "403 Forbidden" problem occur regularly until I made an additional settings change on the phone. Open the Internet Explorer browser and then use the right soft key to open the Menu. Scroll down to tools--options--connections. On that page, I changed the "Select Network:" setting from "WAP Network" to "The Internet" and I haven't seen the "403 Forbidden" error since. Fingers are crossed, but that's been at least a week ago.
Hope this helps someone. I already loved the phone, and do so even more now.