Bug#560142: The cause of ipv6 Problems with java
The update to netbase installs a new sysctl option to the system:
enygma@whitelight:~$ cat /etc/sysctl.d/bindv6only.conf
# This sysctl sets the default value of the IPV6_V6ONLY socket option.
# When disabled, IPv6 sockets will also be able to send and receive IPv4
# traffic with addresses in the form ::ffff:192.0.2.1 and daemons
# on IPv6 sockets will also accept IPv4 connections.
# When IPV6_V6ONLY is enabled, daemons interested in both IPv4 and IPv6
# connections must open two listening sockets.
# This is the default behaviour of all modern operating systems.
net.ipv6.bindv6only = 1
This option makes it not possible to use the ::ffff::ip style mapped
addresses anymore, however, this is the default of the java virtual
machine, unless the specified define is used to suppress ipv6.
Setting the sysctl option to 0 makes java behave normal again.