diff -ur src5.1.3.orig/YACS_SRC_5.1.3/adm/unix/config_files/ac_linker_options.m4 src5.1.3/YACS_SRC_5.1.3/adm/unix/config_files/ac_linker_options.m4
--- src5.1.3.orig/YACS_SRC_5.1.3/adm/unix/config_files/ac_linker_options.m4	2010-03-08 20:39:54.160326435 +0100
+++ src5.1.3/YACS_SRC_5.1.3/adm/unix/config_files/ac_linker_options.m4	2010-03-08 20:40:58.590323448 +0100
@@ -23,6 +23,10 @@
 
   AC_CHECKING(for LIB_LOCATION_SUFFIX)
   LIB_LOCATION_SUFFIX=""
+  case "$build_cpu" in
+  x86_64*)  LIB_LOCATION_SUFFIX="64" ;;
+  *)        LIB_LOCATION_SUFFIX="" ;;
+  esac
   AC_SUBST(LIB_LOCATION_SUFFIX)
   AC_MSG_RESULT(LIB_LOCATION_SUFFIX is $LIB_LOCATION_SUFFIX)