[boost] asio and vc8.0 Link Error

From: Ian Baxter (ibaxter_at_[hidden])
Date: 2006-01-25 22:06:15

Asio when compiled in a mixed assembly with VS 8 produces a link error 
(LNK2022) because of an undefined struct in error.hpp.

changing line 288 error.hpp to this:
struct unspecified_bool_type_t{ };

fixes the problem.

Cheers