Index: app/src/processing/app/Preferences.java
===================================================================
--- app/src/processing/app/Preferences.java	(revision 5415)
+++ app/src/processing/app/Preferences.java	(working copy)
@@ -154,9 +154,13 @@
     // start by loading the defaults, in case something
     // important was deleted from the user prefs
     try {
-      load(Base.getLibStream("preferences.txt"));
+      if (commandLinePrefs != null) {
+        load(new FileInputStream(new File(commandLinePrefs)));
+      } else {
+        load(Base.getLibStream("preferences.txt"));
+      }
     } catch (Exception e) {
-      Base.showError(null, "Could not read default settings.\n" +
+      Base.showError(null, "Could not read default settings.\n " +
                            "You'll need to reinstall Processing.", e);
     }
 
Index: app/src/processing/app/Commander.java
===================================================================
--- app/src/processing/app/Commander.java	(revision 5415)
+++ app/src/processing/app/Commander.java	(working copy)
@@ -136,6 +136,8 @@
           complainAndQuit(platformStr + " should instead be " + 
                           "'windows', 'macosx', or 'linux'.");          
         }
+      } else if (arg.startsWith(preferencesArg)) {
+        preferencesPath = arg.substring(preferencesArg.length());
       } else if (arg.startsWith(sketchArg)) {
         sketchFolder = arg.substring(sketchArg.length());
         File sketchy = new File(sketchFolder);
@@ -294,4 +296,4 @@
     out.println();
     out.println("--preferences=<file> Specify a preferences file to use (optional).");
   }
-}
\ No newline at end of file
+}