I'm using a development server which I currently only have IPv6 connectivity to, and I'm working on a rails application.
I tried to use
bundle exec rails s -e development -p 3003 -d
tcp 0 0 0.0.0.0:3003 0.0.0.0:* LISTEN 27165/ruby
:; ruby --version
ruby 1.9.3p0 (2011-10-30 revision 33570) [x86_64-linux]
:; rails --version
Figured it out myself,
-b :: will make it listen on both IPv6 and IPv4 (depending on sysctl net.ipv6.bindv6only probably).