Package: libc6 Version: 2.3.2.ds1-11 It seems the weak symbols for res_* are missing on amd64. in resolv/res_data.c there is: #if SHLIB_COMPAT(libresolv, GLIBC_2_0, GLIBC_2_2) weak_alias (__res_query, res_query); It seems the "SHLIB_COMPAT(libresolv, GLIBC_2_0, GLIBC_2_2)" returns false for some reason. If I remove that #if then I properly get the weak symbols. Kurt