--- a/configure.in
+++ b/configure.in
@@ -4625,16 +4625,21 @@ if test "$SYSTEM_JPEG" = 1; then
     AC_TRY_COMPILE([ #include <stdio.h>
                      #include <sys/types.h>
                      #include <jpeglib.h> ],
                    [ #if JPEG_LIB_VERSION < $MOZJPEG
                      #error "Insufficient JPEG library version ($MOZJPEG required)."
                      #endif ],
                    SYSTEM_JPEG=1,
                    [SYSTEM_JPEG= JPEG_CFLAGS= JPEG_LIBS=]) 
+fi
+
+MOZ_LIBJPEG_TURBO=
+if test -z "$SYSTEM_JPEG"; then
+    MOZ_LIBJPEG_TURBO=1
 fi 
 CFLAGS=$_SAVE_CFLAGS
 LDFLAGS=$_SAVE_LDFLAGS
 LIBS=$_SAVE_LIBS
 
 if test -n "${JPEG_DIR}" -a -d "${JPEG_DIR}" -a "$SYSTEM_JPEG" = 1; then
     JPEG_CFLAGS="-I${JPEG_DIR}/include"
     JPEG_LIBS="-L${JPEG_DIR}/lib ${JPEG_LIBS}"
@@ -4817,17 +4822,16 @@ MOZ_MEDIA=
 MOZ_WEBM=1
 VPX_AS=
 VPX_ASFLAGS=
 VPX_AS_DASH_C_FLAG=
 VPX_AS_CONVERSION=
 VPX_ASM_SUFFIX=
 VPX_X86_ASM=
 VPX_ARM_ASM=
-MOZ_LIBJPEG_TURBO=1
 LIBJPEG_TURBO_AS=
 LIBJPEG_TURBO_ASFLAGS=
 LIBJPEG_TURBO_X86_ASM=
 LIBJPEG_TURBO_X64_ASM=
 MOZ_PANGO=1
 MOZ_PERMISSIONS=1
 MOZ_PLACES=1
 MOZ_PREF_EXTENSIONS=1