diff --git a/configure b/configure
index 7625054..7688b20 100755
--- a/configure
+++ b/configure
@@ -2950,6 +2950,9 @@ case "$target_arch2" in
     exit 1
   ;;
 esac
+if test "$xen" = yes; then
+  target_phys_bits=64
+fi
 echo "TARGET_ARCH=$TARGET_ARCH" >> $config_target_mak
 target_arch_name="`echo $TARGET_ARCH | tr '[:lower:]' '[:upper:]'`"
 echo "TARGET_$target_arch_name=y" >> $config_target_mak