Index: /trunk/configure
===================================================================
--- /trunk/configure	(revision 23544)
+++ /trunk/configure	(revision 23545)
@@ -121,4 +121,5 @@
 INCPNG=""
 LIBPNG="-lpng"
+CXX_FLAGS=""
 if [ "$OS" = "freebsd" ]; then
   INCCURL="-I/usr/local/include"
@@ -257,6 +258,6 @@
   cat $ODIR.tmp_src.cc >> $LOG
   echo "using the following command line:" >> $LOG
-  echo "$CXX -O -Wall -o $ODIR.tmp_out $ODIR.tmp_src.cc \"$1\"" >> $LOG
-  $CXX -g -O -Wall -o $ODIR.tmp_out $ODIR.tmp_src.cc $1 >> $LOG 2>&1
+  echo "$CXX $CXX_FLAGS -g -O -Wall -o $ODIR.tmp_out $ODIR.tmp_src.cc \"$1\"" >> $LOG
+  $CXX $CXX_FLAGS -g -O -Wall -o $ODIR.tmp_out $ODIR.tmp_src.cc $1 >> $LOG 2>&1
   if [ $? -ne 0 ]; then
     if [ -z "$4" ]; then
@@ -1904,11 +1905,23 @@
     10\.*)
       darwin_ver="10.6"
+      sdk=/Developer/SDKs/MacOSX10.5.sdk
+      CXX_FLAGS="-mmacosx-version-min=10.5 -isysroot $sdk -Wl,-syslibroot,$sdk"
+      test "$CC" = "gcc" && CC="gcc-4.0"
+      test "$CXX" = "g++" && CXX="g++-4.0"
       ;;
     9\.*)
       darwin_ver="10.5"
+      sdk=/Developer/SDKs/MacOSX10.5.sdk
+      CXX_FLAGS="-mmacosx-version-min=10.5 -isysroot $sdk -Wl,-syslibroot,$sdk"
+      test "$CC" = "gcc" && CC="gcc-4.0"
+      test "$CXX" = "g++" && CXX="g++-4.0"
       cnf_append "VBOX_WITHOUT_VBOXPYTHON_FOR_OSX_10_6" "1"
       ;;
     8\.*)
       darwin_ver="10.4"
+      sdk=/Developer/SDKs/MacOSX10.4u.sdk 
+      CXX_FLAGS="-mmacosx-version-min=10.4 -isysroot $sdk -Wl,-syslibroot,$sdk"
+      test "$CC" = "gcc" && CC="gcc-4.0"
+      test "$CXX" = "g++" && CXX="g++-4.0"
       cnf_append "VBOX_WITH_COCOA_QT" ""
       cnf_append "VBOX_WITHOUT_VBOXPYTHON_FOR_OSX_10_6" "1"
@@ -1920,5 +1933,5 @@
       ;;
   esac
-  log_success "found version $darwin_ver"
+  log_success "found version $darwin_ver (SDK: $sdk)"
 }
 
@@ -2258,4 +2271,8 @@
 [ $WITH_HARDENING -eq 2 ] && cnf_append "VBOX_WITH_HARDENING" "2"
 
+# Darwin-specific
+if [ "$OS" = "darwin" ]; then
+  check_darwinversion
+fi
 # the tools
 check_gcc
@@ -2326,9 +2343,4 @@
     cnf_append "VBOX_WITH_WEBSERVICES" ""
   fi
-fi
-
-# Darwin-specific
-if [ "$OS" = "darwin" ]; then
-  check_darwinversion
 fi