diff -rup gnocl-0.9.96.orig/src/Makefile gnocl-0.9.96/src/Makefile
--- gnocl-0.9.96.orig/src/Makefile	2013-01-31 10:52:21.000000000 +0100
+++ gnocl-0.9.96/src/Makefile	2013-09-09 22:58:42.511541653 +0200
@@ -142,15 +142,15 @@ clean:
 	rm -f $(GTK_OBJ) $(PACKAGE_NAME).so
 
 install:
-	./install.tcl $(PACKAGE_REQUIRE_NAME) $(VERSION) $(PACKAGE_NAME) install
+	./install.tcl $(PACKAGE_REQUIRE_NAME) $(VERSION) $(PACKAGE_NAME) install $(DESTDIR)
 
 
 uninstall:
-	./install.tcl $(PACKAGE_REQUIRE_NAME) $(VERSION) $(PACKAGE_NAME) uninstall
+	./install.tcl $(PACKAGE_REQUIRE_NAME) $(VERSION) $(PACKAGE_NAME) uninstall $(DESTDIR)
 
 reinstall:
-	./install.tcl $(PACKAGE_REQUIRE_NAME) $(VERSION) $(PACKAGE_NAME) uninstall
-	./install.tcl $(PACKAGE_REQUIRE_NAME) $(VERSION) $(PACKAGE_NAME) install
+	./install.tcl $(PACKAGE_REQUIRE_NAME) $(VERSION) $(PACKAGE_NAME) uninstall $(DESTDIR)
+	./install.tcl $(PACKAGE_REQUIRE_NAME) $(VERSION) $(PACKAGE_NAME) install $(DESTDIR)
 
 test:
 	( \
@@ -161,10 +161,12 @@ test:
 
 devinstall:
 	ar cr libgnocl-$(VERSION).a $(GTK_OBJ)
-	cp gnocl*.h /usr/include
-	cp libgnocl*.a /usr/lib
+	test -d $(DESTDIR)/usr/include || mkdir -p $(DESTDIR)/usr/include
+	cp gnocl.h gnoclparams.h $(DESTDIR)/usr/include
+	test -d $(DESTDIR)/usr/lib || mkdir -p $(DESTDIR)/usr/lib
+	cp libgnocl*.a $(DESTDIR)/usr/lib
 	rm libgnocl*.a
 
 devuninstall:
-	rm /usr/include/gnocl*.h
-	rm /usr/lib/libgnocl*.a
+	rm -f $(DESTDIR)/usr/include/gnocl*.h
+	rm -f $(DESTDIR)/usr/lib/libgnocl*.a
diff -rup gnocl-0.9.96.orig/src/install.tcl gnocl-0.9.96/src/install.tcl
--- gnocl-0.9.96.orig/src/install.tcl	2013-01-31 10:52:21.000000000 +0100
+++ gnocl-0.9.96/src/install.tcl	2013-09-09 23:01:54.721552241 +0200
@@ -36,13 +36,13 @@ proc date { {i date} } {
 }
 
 # error checking
-if { $argc != 4 } {
+if { $argc < 4 || $argc > 5 } {
    set name [file tail $argv0]
    error "Wrong number of args.\nUsage: $name package version install/uninstall"
 }
 
 # get parameters
-foreach {package version name what} $argv { break }
+foreach {package version name what dest} $argv { break }
 
 # get installation directory
 set dir [info library]
@@ -51,7 +51,7 @@ set dir [info library]
 set destDir [file join $dir $name$version]
 switch -- $what {
    "install"   {
-       if { [file exists $destDir] } {
+       if { [file exists $dest$destDir] } {
            puts "$destDir exists already. Aborting installation."
            exit -1
            }
@@ -70,18 +70,18 @@ switch -- $what {
            puts $fp "package ifneeded $package $version \[list load \[file join \$dir $name.so\]\]"
            close $fp
            puts "Creating $destDir"
-           file mkdir $destDir
+           file mkdir $dest$destDir
            set files [glob *.so]
            lappend files pkgIndex.tcl
            foreach file $files {
                puts "Copying $file"
-               file copy $file $destDir
-               exec chmod 444 $file
+               file copy $file $dest$destDir
+               exec chmod 644 $file
                }
         }
    "uninstall" {
        puts "Deleting $destDir"
-       file delete -force $destDir
+       file delete -force $dest$destDir
        }
    default {
        error "unknown type \"$what\" must be install, test or uninstall"