Reproducing this problem is easy on modern windows systems by turning of the ipv4 stack and leaving ipv6 on, this way your pc will only use your native IPv6 connection, if ipv6 doesn't work correctly in your home/city/country, it doesn't mmean its broken for us al,even more, some ONLY have ipv6 access and they NEED to tunnel their ipv4 over their IPv6 connection. Because minecraft turns IPv6 completly of, they also BREAK the way the OS can tunnel data over an IPV6 only network to the IPv4 part of the world, breaking something what worked for them in the past.
IPv6 has worked for Minecraft in the past and mojangs decision to disable ipv6 broke for many ipv6 only networking users with the proper transition techniques in place.
For your information, the method to connect to IPv4 address from IPv6 only areas is called NAT64 (rfc6146), this works by translating the IPv4 address from the target to IPv6 addresses representing the same address, this way the IPv6 host only sees connectivity on the IPv6 network and CANNOT use IPv4 sockets to the outside world, even though he can connect to IPv4 host fine thanks to the NAT64. Minecraft CANNOT use this with the setting of disable IPv6, something mojang didn't see coming when they disabled it
The bug still exists inside minecraft 15w42a, the reason Mojang decided may be related to the java multicast problem of settings the TTL to zero without it, http://stackoverflow.com/q/139909/1542723, however Mojang can use ipv6 multicast addresses to fix the real problem instead of turning the ipv6 stack of
MC-12847
MCL-9993
I also confirmed the bug, whit 2 stars and 32 dye, you can make almost 4 stacks of nether stars
does it also happen with a clean minecraft.jar?
I can confirm this bug
did you played the game with an 1.5.2 minecraft before?
Reproducing this problem is easy on modern windows systems by turning of the ipv4 stack and leaving ipv6 on, this way your pc will only use your native IPv6 connection, if ipv6 doesn't work correctly in your home/city/country, it doesn't mmean its broken for us al,even more, some ONLY have ipv6 access and they NEED to tunnel their ipv4 over their IPv6 connection. Because minecraft turns IPv6 completly of, they also BREAK the way the OS can tunnel data over an IPV6 only network to the IPv4 part of the world, breaking something what worked for them in the past.
IPv6 has worked for Minecraft in the past and mojangs decision to disable ipv6 broke for many ipv6 only networking users with the proper transition techniques in place.
For your information, the method to connect to IPv4 address from IPv6 only areas is called NAT64 (rfc6146), this works by translating the IPv4 address from the target to IPv6 addresses representing the same address, this way the IPv6 host only sees connectivity on the IPv6 network and CANNOT use IPv4 sockets to the outside world, even though he can connect to IPv4 host fine thanks to the NAT64. Minecraft CANNOT use this with the setting of disable IPv6, something mojang didn't see coming when they disabled it
The bug still exists inside minecraft 15w42a, the reason Mojang decided may be related to the java multicast problem of settings the TTL to zero without it, http://stackoverflow.com/q/139909/1542723, however Mojang can use ipv6 multicast addresses to fix the real problem instead of turning the ipv6 stack of