Boost Test: Add information to messages

The documentation says it should be possible to handle the message after a test as a stream:

http://ift.tt/1BTG0Th

But when I try this:

BOOST_REQUIRE_MESSAGE( testSomething,"connected test failed between "<< a "->"<<b );

I get an Error:

c++   -DBOOST_TEST_DYN_LINK -I/opt/boost/boost157/include    -std=c++0x  -MMD -MT test.cpp.o -MF test

...

error: expected ')' before string constant