The boost serialization library tests use boost.filesystem. A number of test scenarios in the serialization library tests suite are really manifestations of failures in the boost filesystem library. a) msvc- 9.0~wm5~stlport5.2 - this combination fails at some level for lack of a file "io.h". b) does filesystem really require RTTI? at least a subset (and maybe more) of the serialization library tests should function in the absense of RTTI but now they all fail since all the tests use filesystem and this in turn depends upon RTTI. Robert Ramey