Hello everyone, I am new to Boost. I am using Borland C++ Builder 6 (bcc32 v5.6). Now I wanted to use the ptr_container/ptr_vector: So I included . that's where the trouble starts, without actually using a ptr_vector. Compiling leaves me with errors in reversible_ptr_container.hpp: "reversible_ptr_container.hpp(487): E2404 Dependant type qualifier 'reversible_ptr_container' has no member type named 'allow_null'." To be honest: I have no clue, what to do to to get rid of that error. I guess ptr_vector should work on the bcc32, at least I was not able to find anything related to this error searching this mailing-list's archive and elsewhere with google. I imagine I might have set some compiler's settings wrong or something, but I don't know. If anyone could help me out on this, I'd be very thankful! Ivo.