Hi, I think I stumbled over a problem in the boost unit test library. I'm running MSVC 2008 SP1. Maybe also worth mentioning is, that I use _HAS_TR1=0 with any msvc build. Also I compile boost using bjam define=_HAS_TR1=0 ... Well straight to the problem: this code (boost\test\utils\basic_cstring\basic_cstring.hpp, around line 170) template<typename CharT> inline basic_cstring<CharT>::basic_cstring( std_string const& s ) : m_begin( s.c_str() ) , m_end( m_begin + s.size() ) { } will result in a corrupted basic_cstring, if the source string s goes out of scope, which is the case here ( \boost\test\impl\unit_test_main.ipp, around line 179 ) ... int BOOST_TEST_DECL unit_test_main( init_unit_test_func init_func, int argc, char* argv[] ) { try { framework::init( init_func, argc, argv ); if( !runtime_config::test_to_run().is_empty() ) { test_case_filter filter( runtime_config::test_to_run() ); // <--- parameter will become corrupted traverse_test_tree( framework::master_test_suite().p_id, filter ); } ... because of the temporal std::string return from retrieve_parameter (boost\test\impl\unit_test_parameters.ipp, around line 353 ) const_string test_to_run() { return retrieve_parameter( TESTS_TO_RUN, s_cla_parser, s_empty ); } as quick and very very dirty fix I currently use: test_to_run() { static std::string TTR = retrieve_parameter( TESTS_TO_RUN, s_cla_parser, s_empty ); return TTR; } However, I would welcome, if somebody could supply a more suitable solutions. Best Jochen