The Android user-space isn't GPL licensed but mostly licensed under ASL2.0. They don't have to make the source available on request. But people are allowed to distribute the binaries and to distribute the source if they have it. The Android Linux kernel is GPLv2 licensed and the source, including Honeycomb, is available at http://android.git.kernel.org/.
Didn't you read about the recent DNS rebinding attack on wireless routers? It works on routers with remote access disabled but with the default administration password. The attack basically tricks the user's browser into attacking the local administration interface.
This is tricking the little kid inside the car to unlock it for you.
DNSSEC requires EDNS. EDNS allows for UDP packets larger than the original 512-byte limit of DNS over UDP. There could be problems with fragmented packets which are larger than the MTU. Some experiments show that responses with DNSSEC and IPv6 are larger than 512-bytes but smaller than typical MTU of 1500 bytes.
There are some old firewall equipment that mistakenly prohibits DNS packets longer 512 bytes over UDP but those have caused problems for a while.
DNS uses UDP by default. If the response is too big for UDP, then it switches to TCP. The limit for UDP packets used to be 512 bytes but extensions allow the size to be much larger. Old firewalls think that 512-bytes is the limit of DNS over UDP and block any longer packets.