Index: lucene/analysis/common/src/java/org/apache/lucene/analysis/util/StemmerUtil.java
===================================================================
--- lucene/analysis/common/src/java/org/apache/lucene/analysis/util/StemmerUtil.java	(revision 1525521)
+++ lucene/analysis/common/src/java/org/apache/lucene/analysis/util/StemmerUtil.java	(working copy)
@@ -87,10 +87,12 @@
    * @return length of input buffer after deletion
    */
   public static int delete(char s[], int pos, int len) {
-    if (pos < len) 
+    if (pos < len) {
       System.arraycopy(s, pos + 1, s, pos, len - pos - 1);
-    
-    return len - 1;
+      return len - 1;
+    } else {
+      return len;
+    }
   }
   
   /**
@@ -103,9 +105,12 @@
    * @return length of input buffer after deletion
    */
   public static int deleteN(char s[], int pos, int len, int nChars) {
-    // TODO: speed up, this is silly
-    for (int i = 0; i < nChars; i++)
-      len = delete(s, pos, len);
-    return len;
+    if (pos < len) {
+      nChars = pos + nChars > len ? len - pos : nChars;
+      System.arraycopy(s, pos + nChars, s, pos, len - pos - nChars);
+      return len - nChars;
+    } else {
+      return len;
+    }
   }
 }