Hi ! Please find a patch attached which tries to fix 2 issues: First, signed/unsigned mismatch in boost/iostreams/char_traits.hpp The fix is to change is_good(int) to is_good(std::wint_t) Second, boost/iostreams/filter/symmetric_filter_adapter.hpp contains two template implementations without corresponding definitions. gcc-3.4.x chokes on them. Yours, Jürgen -- * Dipl.-Math. Jürgen Hunold ! Institut für Verkehrswesen, Eisenbahnbau * voice: ++49 511 762-2529 ! und -betrieb, Universität Hannover * fax : ++49 511 762-3001 ! Appelstrasse 9a, D-30167 Hannover * hunold@ive.uni-hannover.de ! www.ive.uni-hannover.de