I have got an error while building debian package for iceweasel

dpkg-buildpackage: source package is iceweasel
dpkg-buildpackage: source version is 2.0.0.3.orig-1
dpkg-buildpackage: source changed by root <root@boss.boss.lan>
dpkg-buildpackage: host architecture i386
dpkg-buildpackage: source version without epoch 2.0.0.3.orig-1
 fakeroot debian/rules clean
dh_testdir
dh_testroot
rm -f build-stamp
# Add here commands to clean up after the build process.
/usr/bin/make distclean
make[1]: Entering directory `/root/Desktop/iceweasel-new/iceweasel-2.0.0.3.orig'
make[1]: *** No rule to make target `distclean'.  Stop.
make[1]: Leaving directory `/root/Desktop/iceweasel-new/iceweasel-2.0.0.3.orig'
make: [clean] Error 2 (ignored)
cp -f /usr/share/misc/config.sub config.sub
cp -f /usr/share/misc/config.guess config.guess
dh_clean  --exclude ./gfx/src/ps/nsFontMetricsPS.cpp.orig --exclude ./config/system-headers.orig
 dpkg-source -b iceweasel-2.0.0.3.orig
dpkg-source: building iceweasel in iceweasel_2.0.0.3.orig-1.tar.gz
dpkg-source: building iceweasel in iceweasel_2.0.0.3.orig-1.dsc
 debian/rules build
dh_testdir
# Add here commands to configure the package.
./configure --host=i486-linux-gnu --build=i486-linux-gnu --prefix=/usr --mandir=\${prefix}/share/man --infodir=\${prefix}/share/info CFLAGS="-Wall -g -O2" LDFLAGS="-Wl,-z,defs"
configure: warning: CFLAGS=-Wall\ -g\ -O2: invalid host type
configure: warning: LDFLAGS=-Wl,-z,defs: invalid host type
configure: error: can only configure for one host and one target at a time
make: *** [config.status] Error 1