Index: src/java/org/apache/hadoop/dfs/QuotaExceededException.java
===================================================================
--- src/java/org/apache/hadoop/dfs/QuotaExceededException.java	(revision 664181)
+++ src/java/org/apache/hadoop/dfs/QuotaExceededException.java	(working copy)
@@ -46,7 +46,7 @@
   public String getMessage() {
     String msg = super.getMessage();
     if (msg == null) {
-      return "The quota" + pathName==null?"":(" of " + pathName) + 
+      return "The quota" + (pathName==null?"":(" of " + pathName)) + 
           " is exceeded: quota=" + quota + " count=" + count;
     } else {
       return msg;
Index: src/java/org/apache/hadoop/dfs/FSImage.java
===================================================================
--- src/java/org/apache/hadoop/dfs/FSImage.java	(revision 664181)
+++ src/java/org/apache/hadoop/dfs/FSImage.java	(working copy)
@@ -786,7 +786,9 @@
         }
         if (path.length() == 0) { // it is the root
           // update the root's attributes
-          fsDir.rootDir.setQuota(quota);
+          if (quota != -1) {
+            fsDir.rootDir.setQuota(quota);
+          }
           fsDir.rootDir.setModificationTime(modificationTime);
           fsDir.rootDir.setPermissionStatus(permissions);
           continue;