diff --git a/modules/profiles/clone-config.nix b/modules/profiles/clone-config.nix
new file mode 100644
index 00000000000..69f8537e133
--- /dev/null
+++ b/modules/profiles/clone-config.nix
@@ -0,0 +1,100 @@
+{ config, pkgs, modules, ... }:
+
+with pkgs.lib;
+
+let
+
+  # Location of the repository on the harddrive
+  nixosPath = toString ../..;
+
+  # Check if the path is from the NixOS repository
+  isNixOSFile = path:
+    let s = toString path; in
+      removePrefix nixosPath s != s;
+
+  # Copy modules given as extra configuration files.  Unfortunately, we
+  # cannot serialized attribute set given in the list of modules (that's why
+  # you should use files).
+  moduleFiles =
+    filter isPath modules;
+
+  # Partition module files because between NixOS and non-NixOS files.  NixOS
+  # files may change if the repository is updated.
+  partitionedModuleFiles =
+    let p = partition isNixOSFile moduleFiles; in
+    { nixos = p.right; others = p.wrong; };
+
+  # Path transformed to be valid on the installation device.  Thus the
+  # device configuration could be rebuild.
+  relocatedModuleFiles =
+    let
+      relocateNixOS = path:
+        "<nixos" + removePrefix nixosPath (toString path) + ">";
+      relocateOthers = null;
+    in
+      { nixos = map relocateNixOS partitionedModuleFiles.nixos;
+        others = []; # TODO: copy the modules to the install-device repository.
+      };
+
+  # A dummy /etc/nixos/configuration.nix in the booted CD that
+  # rebuilds the CD's configuration (and allows the configuration to
+  # be modified, of course, providing a true live CD).  Problem is
+  # that we don't really know how the CD was built - the Nix
+  # expression language doesn't allow us to query the expression being
+  # evaluated.  So we'll just hope for the best.
+  configClone = pkgs.writeText "configuration.nix"
+    ''
+      { config, pkgs, ... }:
+
+      {
+        require = [ ${toString config.installer.cloneConfigIncludes} ];
+      }
+    '';
+
+in
+
+{
+
+  options = {
+
+    installer.cloneConfig = mkOption {
+      default = true;
+      description = ''
+        Try to clone the installation-device configuration by re-using it's
+        profile from the list of imported modules.
+      '';
+    };
+
+    installer.cloneConfigIncludes = mkOption {
+      default = [];
+      example = [ "./nixos/modules/hardware/network/rt73.nix" ];
+      description = ''
+        List of modules used to re-build this installation device profile.
+      '';
+    };
+
+  };
+
+  config = {
+
+    installer.cloneConfigIncludes =
+      relocatedModuleFiles.nixos ++ relocatedModuleFiles.others;
+
+    boot.postBootCommands =
+      ''
+        # Provide a mount point for nixos-install.
+        mkdir -p /mnt
+
+        ${optionalString config.installer.cloneConfig ''
+          # Provide a configuration for the CD/DVD itself, to allow users
+          # to run nixos-rebuild to change the configuration of the
+          # running system on the CD/DVD.
+          if ! [ -e /etc/nixos/configuration.nix ]; then
+            cp ${configClone} /etc/nixos/configuration.nix
+          fi
+       ''}
+      '';
+
+  };
+
+}
diff --git a/modules/profiles/installation-device.nix b/modules/profiles/installation-device.nix
index 2ed5a63887f..28c6b09670b 100644
--- a/modules/profiles/installation-device.nix
+++ b/modules/profiles/installation-device.nix
@@ -3,88 +3,19 @@
 
 with pkgs.lib;
 
-let
-  # Location of the repository on the harddrive
-  nixosPath = toString ../..;
-
-  # Check if the path is from the NixOS repository
-  isNixOSFile = path:
-    let s = toString path; in
-      removePrefix nixosPath s != s;
-
-  # Copy modules given as extra configuration files.  Unfortunately, we
-  # cannot serialized attribute set given in the list of modules (that's why
-  # you should use files).
-  moduleFiles =
-    filter isPath modules;
-
-  # Partition module files because between NixOS and non-NixOS files.  NixOS
-  # files may change if the repository is updated.
-  partitionedModuleFiles =
-    let p = partition isNixOSFile moduleFiles; in
-    { nixos = p.right; others = p.wrong; };
-
-  # Path transformed to be valid on the installation device.  Thus the
-  # device configuration could be rebuild.
-  relocatedModuleFiles =
-    let
-      relocateNixOS = path:
-        "<nixos" + removePrefix nixosPath (toString path) + ">";
-      relocateOthers = null;
-    in
-      { nixos = map relocateNixOS partitionedModuleFiles.nixos;
-        others = []; # TODO: copy the modules to the install-device repository.
-      };
-
-  # A dummy /etc/nixos/configuration.nix in the booted CD that
-  # rebuilds the CD's configuration (and allows the configuration to
-  # be modified, of course, providing a true live CD).  Problem is
-  # that we don't really know how the CD was built - the Nix
-  # expression language doesn't allow us to query the expression being
-  # evaluated.  So we'll just hope for the best.
-  configClone = pkgs.writeText "configuration.nix"
-    ''
-      { config, pkgs, ... }:
-
-      {
-        require = [
-          ${toString config.installer.cloneConfigIncludes}
-        ];
-      }
-    '';
-in
-
 {
-  imports = [
-    # Enable devices which are usually scanned, because we don't know the
-    # target system.
-    ../installer/scan/detected.nix
-    ../installer/scan/not-detected.nix
-  ];
+  imports =
+    [ # Enable devices which are usually scanned, because we don't know the
+      # target system.
+      ../installer/scan/detected.nix
+      ../installer/scan/not-detected.nix
 
-  options = {
-  
-    installer.cloneConfig = mkOption {
-      default = true;
-      description = ''
-        Try to clone the installation-device configuration by re-using it's
-        profile from the list of imported modules.
-      '';
-    };
-
-    installer.cloneConfigIncludes = mkOption {
-      default = [];
-      example = [ "./nixos/modules/hardware/network/rt73.nix" ];
-      description = ''
-        List of modules used to re-build this installation device profile.
-      '';
-    };
-
-  };
+      # Allow "nixos-rebuild" to work properly by providing
+      # /etc/nixos/configuration.nix.
+      ./clone-config.nix
+    ];
 
   config = {
-    installer.cloneConfigIncludes =
-      relocatedModuleFiles.nixos ++ relocatedModuleFiles.others;
 
     # Show the manual.
     services.nixosManual.showManual = true;
@@ -99,19 +30,6 @@ in
     # the full glibcLocales package.
     i18n.supportedLocales = ["en_US.UTF-8/UTF-8" "en_US/ISO-8859-1"];
 
-    boot.postBootCommands =
-      ''
-        # Provide a mount point for nixos-install.
-        mkdir -p /mnt
-
-        ${optionalString config.installer.cloneConfig ''
-          # Provide a configuration for the CD/DVD itself, to allow users
-          # to run nixos-rebuild to change the configuration of the
-          # running system on the CD/DVD.
-          cp ${configClone} /etc/nixos/configuration.nix
-       ''}
-      '';
-
     # Some more help text.
     services.mingetty.helpLine =
       ''