I've had my N900 working great with IPv6 on T-Mobile for quite awhile, and have just recently been trying to tether my laptop to it, but haven't had any luck. I run "ipv6-share start" on the N900, and then "dhcpcd usb0" on the laptop, and this is what I get:

dhcpcd: version 5.2.2 starting
dhcpcd: usb0: checking for 169.254.208.219
dhcpcd: usb0: using IPv4LL address 169.254.208.219
dhcpcd: forking to background

Why is it giving me that address? I also have a valid IPv6 address, but no name servers in /etc/resolv.conf, so nothing gets resolved. I can ssh into the N900 using it's IPv6 address, but I can't connect to anything on the Internet by name, IPv4 address, or IPv6 address. Trying to ssh to an IPv6 address results in "Name or service not known" and trying to ssh to an IPv4 address results in "Network is unreachable".

According to whois.arin.net (using the whois command), the IPv4 address I'm getting is a link local address, and "Hosts obtain these addresses by auto-configuration, such as when a DHCP server cannot be found", but it's obviously finding the N900's DHCP server or it wouldn't be getting the correct IPv6 address (from T-Mobile's 2607:fb90:: block).

Looking at the ipv6-share script, it looks like I should be getting an address between 10.255.255.10 and 10.255.255.100, so why am I getting that link local address instead?