Hi, While using the boost cvs sources on Mac OS X 10.4.2 I have come across the error below: (I'm using the cvs since 1.32 wont build on 10.4 due to apple? removing one of the gcc compiler flags...) In file included from /usr/local/include/boost/archive/detail/basic_oarchive.hpp:25, from /usr/local/include/boost/archive/detail/oserializer.hpp:58, from /usr/local/include/boost/archive/basic_text_oarchive.hpp:32, from /usr/local/include/boost/archive/text_oarchive.hpp:31, from ./zz_cell_zri.h:28, from ./zz_public_cell.h:27, from ./zz_cell_set.h:21, from ./mantra_response.h:32, from ./mantra_request_abstract.h:26, from mantra_request_admin.h:21, from mantra_request_admin.cpp:16: /usr/local/include/boost/archive/basic_archive.hpp:21:2: error: #error "no serialization headers my precede any archive headers" Cheers Chris This message has been checked for viruses but the contents of an attachment may still contain software viruses, which could damage your computer system: you are advised to perform your own checks. Email communications with the University of Nottingham may be monitored as permitted by UK legislation.