diff --git a/build_image.sh b/build_image.sh
index b30493c24e..77dc691d49 100755
--- a/build_image.sh
+++ b/build_image.sh
@@ -274,7 +274,7 @@ sudo sfdisk -H64 -S32 -uS -f "$MBR_IMG" <<EOF
 ;
 EOF
 
-OUTSIDE_OUTPUT_DIR="~/chromeos/src/build/images/${IMAGE_SUBDIR}"
+OUTSIDE_OUTPUT_DIR="${EXTERNAL_TRUNK_PATH}/src/build/images/${IMAGE_SUBDIR}"
 echo "Done.  Image created in ${OUTPUT_DIR}"
 echo "To copy to USB keyfob, outside the chroot, do something like:"
 echo "  ./image_to_usb.sh --from=${OUTSIDE_OUTPUT_DIR} --to=/dev/sdb"
diff --git a/enter_chroot.sh b/enter_chroot.sh
index acfa84682d..ff5c1956df 100755
--- a/enter_chroot.sh
+++ b/enter_chroot.sh
@@ -103,7 +103,7 @@ setup_env
 
 if [ $FLAGS_revision -eq $FLAGS_TRUE ]
 then
-  # Get the subversion revision to pass into the chroot.  
+  # Get the subversion revision to pass into the chroot.
   #
   # This must be determined outside the chroot because (1) there is no
   # svn/git inside the chroot, and (2) if there were it would likely be
@@ -125,10 +125,12 @@ then
   REVISION="CHROMEOS_REVISION=$REVISION"
 fi
 
-# Run command or interactive shell
-sudo chroot "$FLAGS_chroot" sudo -i -u $USER $REVISION "$@"
+# Run command or interactive shell.  Also include the non-chrooted path to
+# the source trunk for scripts that may need to print it (e.g.
+# build_image.sh).
+sudo chroot "$FLAGS_chroot" sudo -i -u $USER $REVISION \
+  EXTERNAL_TRUNK_PATH="${FLAGS_trunk}" "$@"
 
 # Remove trap and explicitly unmount
 trap - EXIT
 teardown_env
-