Added back thread attribute in SIPApplication

Ignore-this: a4f5e4585b3d00de05a6801298919192

darcs-hash:20100910131202-56b4d-008f7fe4fae1d060c426875b11f305ce524393e6
Added missing import

Ignore-this: c9992f975603ec5aec4ad8da653d19ef

darcs-hash:20100910155824-56b4d-63b4e74282cb3f32139a86e308ad93b84b9cade6