I've been doing battle with VC 7.1 and its "'detail' : ambiguous symbol" error messages for a while. The basic problem is that we have a file with, essentially, "using namespace boost; using namespace boost::spirit;" in it. Since VC 7.1 resolves namespace names a bit strangely, these using directives end up being resolved late in the compilation process, so they make lookups of names like "detail" ambiguous.
Confirmed. I got multiple ambiguous detail errors when compiling my program on VC 8.0 Beta2 with most recent boost::spirit. Boost 1.32 did not seem to have that problem though. I solved that in dirty way by extra-qualifying all places where detail ambiguity error occured in my local copy of boost... That was also the reason I posted question about 'detail' namespace conflicts a couple of weeks ago. cheers, Marcin