For the original problem (won't be relevant until you solve the second problem): Can you telnet to google's IP on port 80? What is your IP address (private or public), and how did you get it (DHCP, static)? Sorry I don't know much about cellphone modems, but this seems to be a deeper problem. See what happens when you use a normal modem. What are your other methods of internet connection?
Other than that, the only advice I can give is generic:
- Make sure that there are no dangling iptables rules left over (look at the output of `iptables-save'). You can eliminate everything (I think) by manually running (The '#' prompt indicates you need root privileges)
# iptables -P INPUT ACCEPT
# iptables -P OUTPUT ACCEPT
# iptables -P FORWARD ACCEPT
# iptables -F
# iptables -t nat -P PREROUTING ACCEPT
# iptables -t nat -P OUTPUT ACCEPT
# iptables -t nat -P POSTROUTING ACCEPT
# iptables -t nat -F
# iptables -t mangle -P PREROUTING ACCEPT
# iptables -t mangle -P INPUT ACCEPT
# iptables -t mangle -P OUTPUT ACCEPT
# iptables -t mangle -P POSTROUTING ACCEPT
# iptables -t mangle -F
# iptables -t raw -P PREROUTING ACCEPT
# iptables -t raw -P OUTPUT ACCEPT
# iptables -t raw -F
- Make sure ppp kernel module is loaded (if applicable)
- Make sure any other means of internet connection are not interfering with your modem connection (look very closely at your routing table)
- Compare the information (DNS, IP address, DHCP server, and anything else you find appropriate) from a working implementation (windows) to the broken situation.
For the second problem (lack of device file): Think of what is different from then and now (don't tell me nothing's different, because it is obvious that something
changed). Make sure all appropriate modules are loaded, etc., etc. Try restarting udevd or manually adding the file. Maybe upgrade to a newer version of Mandriva (NOTE: I am not a Mandriva user, and do not fully know about the intricacies of the community/corporate version distinctions. All I know is that there is a Mandriva 2006).