The attached code, which use the multi_index library, produces screens of errors from mpl. The STLfilted log is attached too. Commenting out #include <boost/bind/arg.hpp> makes the error go away, as well as including it after multi_index. This happens with: gcc version 3.3.4 (Debian 1:3.3.4-6sarge1) gcc version 3.4.1 (Debian 3.4.1-4sarge1) The code used to work some time ago, but I can't give the exact date. I've tried too look at the problem, but got lost in MPL internals. - Volodya