diff --git a/libboost.spec b/libboost.spec
index 076a8aa..1f02acc 100644
--- a/libboost.spec
+++ b/libboost.spec
@@ -2,7 +2,7 @@
 %define pckmajver %(echo %version | cut -d. -f1-2 | tr . _)
 Name:          libboost
 Version:       1.69.0
-Release:       1mamba
+Release:       2mamba
 Summary:       Free peer-reviewed portable C++ source libraries
 Group:         System/Libraries
 Vendor:        openmamba
@@ -107,12 +107,12 @@ EXPAT_INCLUDE=%{_includedir} \
 EXPAT_LIBPATH=%{_libdir} \
 ./bjam \
    --prefix=%{_prefix} \
-   --layout=tagged -d2 \
+   --layout=system -d2 \
    runtime-link=shared \
    link=shared,static \
    toolset=gcc \
    variant=release \
-   threading=single,multi \
+   threading=multi \
    debug-symbols=on \
    stage \
 %ifarch x86_64
@@ -134,12 +134,12 @@ EXPAT_LIBPATH=%{_libdir} \
 ./bjam \
    -a \
    --prefix=%{_prefix} \
-   --layout=tagged -d2 \
+   --layout=system -d2 \
    runtime-link=shared \
    link=shared,static \
    toolset=gcc \
    variant=release \
-   threading=single,multi \
+   threading=multi \
    debug-symbols=on \
    stage \
 %ifarch x86_64
@@ -156,12 +156,12 @@ EXPAT_LIBPATH=%{_libdir} \
    --libdir=%{buildroot}%{_libdir} \
    --execprefix=%{buildroot}%{_libexecdir} \
    --includedir=%{buildroot}%{_includedir} \
-   --layout=tagged -d2 \
+   --layout=system -d2 \
    runtime-link=shared \
    link=shared,static \
    toolset=gcc \
    variant=release \
-   threading=single,multi \
+   threading=multi \
    debug-symbols=on \
    install
 
@@ -173,12 +173,12 @@ EXPAT_LIBPATH=%{_libdir} \
    --libdir=%{buildroot}%{_libdir} \
    --execprefix=%{buildroot}%{_libexecdir} \
    --includedir=%{buildroot}%{_includedir} \
-   --layout=tagged -d2 \
+   --layout=system -d2 \
    runtime-link=shared \
    link=shared,static \
    toolset=gcc \
    variant=release \
-   threading=single,multi \
+   threading=multi \
    debug-symbols=on \
    install
    
@@ -224,6 +224,9 @@ EXPAT_LIBPATH=%{_libdir} \
 %{_libdir}/libboost_python36*.so.*
 
 %changelog
+* Mon Feb 11 2019 Silvan Calarco <silvan.calarco@mambasoft.it> 1.69.0-2mamba
+- rebuilt with --threading=multi and --layout=system
+
 * Tue Jan 22 2019 Automatic Build System <autodist@mambasoft.it> 1.69.0-1mamba
 - automatic version update by autodist