Make it static.

src/main/java/com/gmail/nossr50/mcMMO.java

@@ -97,7 +97,7 @@ public class mcMMO extends JavaPlugin {
     public static RepairManager repairManager;
 
     /* Jar Stuff */
-    public File mcmmo;
+    public static File mcmmo;
 
     //File Paths
     public static String mainDirectory;

src/main/java/com/gmail/nossr50/spout/SpoutStuff.java

@@ -54,8 +54,8 @@ public class SpoutStuff {
     private static void writeFile(String theFileName, String theFilePath) {
         try {
             File currentFile = new File(theFilePath + theFileName);
-
-            JarFile jar = new JarFile(plugin.mcmmo);
+            
+            JarFile jar = new JarFile(mcMMO.mcmmo);
             JarEntry entry = jar.getJarEntry("resources/" + theFileName);
             InputStream is = jar.getInputStream(entry);