diff --git a/Makefile b/Makefile
index 85d84e9..b4e7dbf 100644
--- a/Makefile
+++ b/Makefile
@@ -3,7 +3,8 @@ VERSION	= 0.0.0
 SUBDIRS	= data doc po src
 RM	= rm -f
 LN	= ln -f
-TAR	= tar -czvf
+TAR	= tar
+MKDIR	= mkdir -m 0755 -p
 
 
 all: subdirs
@@ -20,7 +21,7 @@ distclean:
 dist:
 	$(RM) -r -- $(PACKAGE)-$(VERSION)
 	$(LN) -s -- . $(PACKAGE)-$(VERSION)
-	@$(TAR) $(PACKAGE)-$(VERSION).tar.gz -- \
+	@$(TAR) -czvf $(PACKAGE)-$(VERSION).tar.gz -- \
 		$(PACKAGE)-$(VERSION)/data/Makefile \
 		$(PACKAGE)-$(VERSION)/data/deforaos-installer.desktop \
 		$(PACKAGE)-$(VERSION)/data/project.conf \
@@ -46,10 +47,21 @@ dist:
 		$(PACKAGE)-$(VERSION)/project.conf
 	$(RM) -- $(PACKAGE)-$(VERSION)
 
+distcheck: dist
+	$(TAR) -xzvf $(PACKAGE)-$(VERSION).tar.gz
+	$(MKDIR) -- $(PACKAGE)-$(VERSION)/objdir
+	$(MKDIR) -- $(PACKAGE)-$(VERSION)/destdir
+	(cd "$(PACKAGE)-$(VERSION)" && $(MAKE) OBJDIR="$$PWD/objdir/")
+	(cd "$(PACKAGE)-$(VERSION)" && $(MAKE) OBJDIR="$$PWD/objdir/" DESTDIR="$$PWD/destdir" install)
+	(cd "$(PACKAGE)-$(VERSION)" && $(MAKE) OBJDIR="$$PWD/objdir/" DESTDIR="$$PWD/destdir" uninstall)
+	(cd "$(PACKAGE)-$(VERSION)" && $(MAKE) OBJDIR="$$PWD/objdir/" distclean)
+	(cd "$(PACKAGE)-$(VERSION)" && $(MAKE) dist)
+	$(RM) -r -- $(PACKAGE)-$(VERSION)
+
 install:
 	@for i in $(SUBDIRS); do (cd "$$i" && $(MAKE) install) || exit; done
 
 uninstall:
 	@for i in $(SUBDIRS); do (cd "$$i" && $(MAKE) uninstall) || exit; done
 
-.PHONY: all subdirs clean distclean dist install uninstall
+.PHONY: all subdirs clean distclean dist distcheck install uninstall
diff --git a/data/Makefile b/data/Makefile
index 9c879fe..d561a66 100644
--- a/data/Makefile
+++ b/data/Makefile
@@ -1,3 +1,4 @@
+OBJDIR	=
 PREFIX	= /usr/local
 DESTDIR	=
 MKDIR	= mkdir -m 0755 -p
diff --git a/doc/Makefile b/doc/Makefile
index 39f5eb4..a5983a4 100644
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -1,4 +1,5 @@
-TARGETS	= installer.1 installer.html
+TARGETS	= $(OBJDIR)installer.1 $(OBJDIR)installer.html
+OBJDIR	=
 PREFIX	= /usr/local
 DESTDIR	=
 RM	= rm -f
@@ -9,11 +10,11 @@ INSTALL	= install
 
 all: $(TARGETS)
 
-installer.1: installer.xml
-	./docbook.sh -P "$(PREFIX)" -- "installer.1"
+$(OBJDIR)installer.1: installer.xml
+	./docbook.sh -P "$(PREFIX)" -- "$(OBJDIR)installer.1"
 
-installer.html: installer.css.xml installer.xml manual.css.xml
-	./docbook.sh -P "$(PREFIX)" -- "installer.html"
+$(OBJDIR)installer.html: installer.css.xml installer.xml manual.css.xml
+	./docbook.sh -P "$(PREFIX)" -- "$(OBJDIR)installer.html"
 
 clean:
 	$(RM) -- $(installer.1_OBJS) $(installer.html_OBJS)
@@ -24,8 +25,8 @@ distclean: clean
 	$(RM) -- $(TARGETS)
 
 install: $(TARGETS)
-	./docbook.sh -P "$(DESTDIR)$(PREFIX)" -i -- "installer.1"
-	./docbook.sh -P "$(DESTDIR)$(PREFIX)" -i -- "installer.html"
+	./docbook.sh -P "$(DESTDIR)$(PREFIX)" -i -- "$(OBJDIR)installer.1"
+	./docbook.sh -P "$(DESTDIR)$(PREFIX)" -i -- "$(OBJDIR)installer.html"
 
 uninstall:
 	./docbook.sh -P "$(DESTDIR)$(PREFIX)" -u -- "installer.1"
diff --git a/doc/docbook.sh b/doc/docbook.sh
index 0caaa39..fda4e2d 100755
--- a/doc/docbook.sh
+++ b/doc/docbook.sh
@@ -27,6 +27,7 @@
 #variables
 PREFIX="/usr/local"
 [ -f "../config.sh" ] && . "../config.sh"
+PROGNAME="docbook.sh"
 #executables
 DEBUG="_debug"
 FOP="fop"
@@ -52,17 +53,24 @@ _docbook()
 	target="$1"
 
 	source="${target%.*}.xml"
+	[ -f "$source" ] || source="${source#$OBJDIR}"
 	ext="${target##*.}"
 	ext="${ext##.}"
 	case "$ext" in
 		html)
 			XSL="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"
+			[ -f "${source%.*}.xsl" ] && XSL="${source%.*}.xsl"
 			[ -f "${target%.*}.xsl" ] && XSL="${target%.*}.xsl"
-			[ -f "${target%.*}.css.xml" ] && XSLTPROC="$XSLTPROC --param custom.css.source \"${target%.*}.css.xml\" --param generate.css.header 1"
+			if [ -f "${target%.*}.css.xml" ]; then
+				XSLTPROC="$XSLTPROC --param custom.css.source \"${target%.*}.css.xml\" --param generate.css.header 1"
+			elif [ -f "${source%.*}.css.xml" ]; then
+				XSLTPROC="$XSLTPROC --param custom.css.source \"${source%.*}.css.xml\" --param generate.css.header 1"
+			fi
 			$DEBUG $XSLTPROC -o "$target" "$XSL" "$source"
 			;;
 		pdf)
 			XSL="http://docbook.sourceforge.net/release/xsl/current/fo/docbook.xsl"
+			[ -f "${source%.*}.xsl" ] && XSL="${source%.*}.xsl"
 			[ -f "${target%.*}.xsl" ] && XSL="${target%.*}.xsl"
 			$DEBUG $XSLTPROC -o "${target%.*}.fo" "$XSL" "$source" &&
 			$DEBUG $FOP -fo "${target%.*}.fo" -pdf "$target"
@@ -73,13 +81,13 @@ _docbook()
 			$DEBUG $XSLTPROC -o "$target" "$XSL" "$source"
 			;;
 		*)
-			echo "$0: $target: Unknown type" 1>&2
+			_error "$target: Unknown type"
 			return 2
 			;;
 	esac
 
 	if [ $? -ne 0 ]; then
-		echo "$0: $target: Could not create page" 1>&2
+		_error "$target: Could not create page"
 		$RM -- "$target"
 		return 2
 	fi
@@ -89,7 +97,7 @@ _docbook()
 #error
 _error()
 {
-	echo "docbook.sh: $@" 1>&2
+	echo "$PROGNAME: $@" 1>&2
 	return 2
 }
 
@@ -97,7 +105,7 @@ _error()
 #usage
 _usage()
 {
-	echo "Usage: docbook.sh [-c|-i|-u][-P prefix] target..." 1>&2
+	echo "Usage: $PROGNAME [-c|-i|-u][-P prefix] target..." 1>&2
 	return 1
 }
 
@@ -153,7 +161,8 @@ while [ $# -gt 0 ]; do
 	case "$ext" in
 		html)
 			instdir="$DATADIR/doc/$ext/$PACKAGE"
-			source="${target%.*}.xml"
+			source="${target#$OBJDIR}"
+			source="${source%.*}.xml"
 			xpath="string(/refentry/refmeta/manvolnum)"
 			section=$($XMLLINT --xpath "$xpath" "$source")
 			if [ $? -eq 0 -a -n "$section" ]; then
@@ -167,7 +176,7 @@ while [ $# -gt 0 ]; do
 			instdir="$MANDIR/man$ext"
 			;;
 		*)
-			echo "$0: $target: Unknown type" 1>&2
+			_error "$target: Unknown type"
 			exit 2
 			;;
 	esac
@@ -177,14 +186,16 @@ while [ $# -gt 0 ]; do
 
 	#uninstall
 	if [ "$uninstall" -eq 1 ]; then
+		target="${target#$OBJDIR}"
 		$DEBUG $RM -- "$instdir/$target"		|| exit 2
 		continue
 	fi
 
 	#install
 	if [ "$install" -eq 1 ]; then
+		source="${target#$OBJDIR}"
 		$DEBUG $MKDIR -- "$instdir"			|| exit 2
-		$DEBUG $INSTALL "$target" "$instdir/$target"	|| exit 2
+		$DEBUG $INSTALL "$target" "$instdir/$source"	|| exit 2
 		continue
 	fi
 
diff --git a/po/Makefile b/po/Makefile
index 035f384..ff057bb 100644
--- a/po/Makefile
+++ b/po/Makefile
@@ -1,4 +1,5 @@
-TARGETS	= Installer.pot fr.mo
+TARGETS	= $(OBJDIR)Installer.pot $(OBJDIR)fr.mo
+OBJDIR	=
 PREFIX	= /usr/local
 DESTDIR	=
 RM	= rm -f
@@ -9,11 +10,11 @@ INSTALL	= install
 
 all: $(TARGETS)
 
-Installer.pot: POTFILES
-	./gettext.sh -P "$(PREFIX)" -- "Installer.pot"
+$(OBJDIR)Installer.pot: POTFILES
+	./gettext.sh -P "$(PREFIX)" -- "$(OBJDIR)Installer.pot"
 
-fr.mo: Installer.pot fr.po
-	./gettext.sh -P "$(PREFIX)" -- "fr.mo"
+$(OBJDIR)fr.mo: $(OBJDIR)Installer.pot fr.po
+	./gettext.sh -P "$(PREFIX)" -- "$(OBJDIR)fr.mo"
 
 clean:
 	$(RM) -- $(Installer.pot_OBJS) $(fr.mo_OBJS)
@@ -24,7 +25,7 @@ distclean: clean
 	$(RM) -- $(TARGETS)
 
 install: $(TARGETS)
-	./gettext.sh -P "$(DESTDIR)$(PREFIX)" -i -- "fr.mo"
+	./gettext.sh -P "$(DESTDIR)$(PREFIX)" -i -- "$(OBJDIR)fr.mo"
 
 uninstall:
 	./gettext.sh -P "$(DESTDIR)$(PREFIX)" -u -- "fr.mo"
diff --git a/po/gettext.sh b/po/gettext.sh
index 11a8805..c3ae919 100755
--- a/po/gettext.sh
+++ b/po/gettext.sh
@@ -70,9 +70,12 @@ _gettext_mo()
 {
 	package="$1"
 	lang="$2"
+	potfile="$3"
+	pofile="$4"
+	mofile="$5"
 
-	_gettext_po "$package" "$lang"				|| return 1
-	$DEBUG $MSGFMT -c -v -o "$lang.mo" "$lang.po"		|| return 1
+	_gettext_po "$package" "$lang" "$potfile" "$pofile"	|| return 1
+	$DEBUG $MSGFMT -c -v -o "$mofile" "$pofile"		|| return 1
 }
 
 
@@ -81,11 +84,13 @@ _gettext_po()
 {
 	package="$1"
 	lang="$2"
+	potfile="$3"
+	pofile="$4"
 
-	if [ -f "$lang.po" ]; then
-		$DEBUG $MSGMERGE -U "$lang.po" "$package.pot"	|| return 1
+	if [ -f "$pofile" ]; then
+		$DEBUG $MSGMERGE -U "$pofile" "$potfile"	|| return 1
 	else
-		$DEBUG $MSGINIT -l "$lang" -o "$lang.po" -i "$package.pot" \
+		$DEBUG $MSGINIT -l "$lang" -o "$pofile" -i "$potfile" \
 								|| return 1
 	fi
 }
@@ -95,8 +100,9 @@ _gettext_po()
 _gettext_pot()
 {
 	package="$1"
+	potfile="$2"
 
-	$DEBUG $XGETTEXT -d "$package" -o "$package.pot" --keyword="_" \
+	$DEBUG $XGETTEXT -d "$package" -o "$potfile" --keyword="_" \
 			--keyword="N_" -f "$POTFILES"		|| return 1
 }
 
@@ -142,7 +148,8 @@ fi
 LOCALEDIR="$PREFIX/share/locale"
 while [ $# -gt 0 ]; do
 	target="$1"
-	lang="${target%%.mo}"
+	source="${target#$OBJDIR}"
+	lang="${source%%.mo}"
 	lang="${lang%%.po}"
 	shift
 
@@ -168,13 +175,32 @@ while [ $# -gt 0 ]; do
 	#create
 	case "$target" in
 		*.mo)
-			_gettext_mo "$PACKAGE" "$lang"		|| exit 2
+			#XXX may not match
+			if [ -n "$OBJDIR" ]; then
+				potfile="$OBJDIR/$PACKAGE.pot"
+			else
+				potfile="$PACKAGE.pot"
+			fi
+			mofile="$target"
+			pofile="${source%%.mo}.po"
+			_gettext_mo "$PACKAGE" "$lang" "$potfile" "$pofile" \
+				"$mofile"			|| exit 2
 			;;
 		*.po)
-			_gettext_po "$PACKAGE" "$lang"		|| exit 2
+			#XXX may not match
+			if [ -n "$OBJDIR" ]; then
+				potfile="$OBJDIR/$PACKAGE.pot"
+			else
+				potfile="$PACKAGE.pot"
+			fi
+			pofile="$target"
+			_gettext_po "$PACKAGE" "$lang" "$potfile" "$pofile" \
+								|| exit 2
 			;;
 		*.pot)
-			_gettext_pot "${target%%.pot}"		|| exit 2
+			package="${source%%.pot}"
+			potfile="$target"
+			_gettext_pot "$package" "$potfile"	|| exit 2
 			;;
 		*)
 			exit 2
diff --git a/po/project.conf b/po/project.conf
index 3df8276..3ffa210 100644
--- a/po/project.conf
+++ b/po/project.conf
@@ -10,4 +10,4 @@ depends=POTFILES
 type=script
 script=./gettext.sh
 install=
-depends=Installer.pot,fr.po
+depends=$(OBJDIR)Installer.pot,fr.po
diff --git a/src/Makefile b/src/Makefile
index 03c033b..bf72dd7 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1,4 +1,5 @@
-TARGETS	= installer
+TARGETS	= $(OBJDIR)installer
+OBJDIR	=
 PREFIX	= /usr/local
 DESTDIR	=
 BINDIR	= $(PREFIX)/bin
@@ -17,18 +18,18 @@ INSTALL	= install
 
 all: $(TARGETS)
 
-installer_OBJS = installer.o main.o
+installer_OBJS = $(OBJDIR)installer.o $(OBJDIR)main.o
 installer_CFLAGS = $(CPPFLAGSF) $(CPPFLAGS) $(CFLAGSF) $(CFLAGS)
 installer_LDFLAGS = $(LDFLAGSF) $(LDFLAGS)
 
-installer: $(installer_OBJS)
-	$(CC) -o installer $(installer_OBJS) $(installer_LDFLAGS)
+$(OBJDIR)installer: $(installer_OBJS)
+	$(CC) -o $(OBJDIR)installer $(installer_OBJS) $(installer_LDFLAGS)
 
-installer.o: installer.c installer.h ../config.h
-	$(CC) -D PREFIX=\"$(PREFIX)\" $(installer_CFLAGS) -c installer.c
+$(OBJDIR)installer.o: installer.c installer.h ../config.h
+	$(CC) -D PREFIX=\"$(PREFIX)\" $(installer_CFLAGS) -o $(OBJDIR)installer.o -c installer.c
 
-main.o: main.c installer.h ../config.h
-	$(CC) $(installer_CFLAGS) -c main.c
+$(OBJDIR)main.o: main.c installer.h ../config.h
+	$(CC) $(installer_CFLAGS) -o $(OBJDIR)main.o -c main.c
 
 clean:
 	$(RM) -- $(installer_OBJS)
@@ -38,7 +39,7 @@ distclean: clean
 
 install: $(TARGETS)
 	$(MKDIR) $(DESTDIR)$(BINDIR)
-	$(INSTALL) -m 0755 installer $(DESTDIR)$(BINDIR)/installer
+	$(INSTALL) -m 0755 $(OBJDIR)installer $(DESTDIR)$(BINDIR)/installer
 
 uninstall:
 	$(RM) -- $(DESTDIR)$(BINDIR)/installer