Patched dns.entropy module which is not thread-safe

Ignore-this: 5c7731b1a6b80c87be154efda5442fdc

darcs-hash:20100107171031-1e3d8-34958a3b8be660bd54d2bc9933f32b45a3361a40
Do not delete the dns module as it is used later

Ignore-this: b28ea3ae5945b724e4ba05b9df80b660

darcs-hash:20100107182759-b22ec-036694bfcf9554ad14fe3c43bea1191d61cf08ee