diff --git a/docker/debian-7-32bit/Dockerfile b/docker/debian-7-32bit/Dockerfile
index b9e903a..c16b36f 100644
--- a/docker/debian-7-32bit/Dockerfile
+++ b/docker/debian-7-32bit/Dockerfile
@@ -14,9 +14,9 @@ RUN apt-get -yq upgrade
 RUN apt-get -yq install bash sudo pkg-config g++ make wget
 
 # upgrade gcc
-RUN apt-get -yq install libgmp-dev libmpfr-dev libmpc-dev
+RUN apt-get -yq install libgmp-dev libmpfr-dev libmpc-dev gcc-multilib
 COPY files/install-gcc.sh /
-RUN /install-gcc.sh
+RUN setarch i686 /install-gcc.sh
 
 # install tools
 RUN apt-get -yq install csh
diff --git a/docker/debian-7-32bit/files/install-gcc.sh b/docker/debian-7-32bit/files/install-gcc.sh
index 74e62c0..e494d8b 100755
--- a/docker/debian-7-32bit/files/install-gcc.sh
+++ b/docker/debian-7-32bit/files/install-gcc.sh
@@ -15,9 +15,7 @@ echo && echo "build and install" && echo
 
 mkdir -p build
 cd build
-[ -f "../configure.done" ] || ( \
-    ../gcc-*/configure --disable-multilib \
-    && touch "../configure.done")
+[ -f "../configure.done" ] || (../gcc-*/configure && touch "../configure.done")
 make -j`nproc`
 make install
 (cd /usr/local/bin && ln gcc cc)
diff --git a/docker/debian-7-64bit/Dockerfile b/docker/debian-7-64bit/Dockerfile
index 511c9eb..6760e90 100644
--- a/docker/debian-7-64bit/Dockerfile
+++ b/docker/debian-7-64bit/Dockerfile
@@ -14,7 +14,7 @@ RUN apt-get -yq upgrade
 RUN apt-get -yq install bash sudo pkg-config g++ make wget
 
 # upgrade gcc
-RUN apt-get -yq install libgmp-dev libmpfr-dev libmpc-dev
+RUN apt-get -yq install libgmp-dev libmpfr-dev libmpc-dev gcc-multilib
 COPY files/install-gcc.sh /
 RUN /install-gcc.sh
 
diff --git a/docker/debian-7-64bit/files/install-gcc.sh b/docker/debian-7-64bit/files/install-gcc.sh
index 74e62c0..e494d8b 100755
--- a/docker/debian-7-64bit/files/install-gcc.sh
+++ b/docker/debian-7-64bit/files/install-gcc.sh
@@ -15,9 +15,7 @@ echo && echo "build and install" && echo
 
 mkdir -p build
 cd build
-[ -f "../configure.done" ] || ( \
-    ../gcc-*/configure --disable-multilib \
-    && touch "../configure.done")
+[ -f "../configure.done" ] || (../gcc-*/configure && touch "../configure.done")
 make -j`nproc`
 make install
 (cd /usr/local/bin && ln gcc cc)