diff --git a/modules/analysis/kuromoji/src/java/org/apache/lucene/analysis/kuromoji/KuromojiTokenizer.java b/modules/analysis/kuromoji/src/java/org/apache/lucene/analysis/kuromoji/KuromojiTokenizer.java
index c3152837f25..02772281ba6 100644
--- a/modules/analysis/kuromoji/src/java/org/apache/lucene/analysis/kuromoji/KuromojiTokenizer.java
+++ b/modules/analysis/kuromoji/src/java/org/apache/lucene/analysis/kuromoji/KuromojiTokenizer.java
@@ -648,7 +648,7 @@ public final class KuromojiTokenizer extends Tokenizer {
           final Position posData2 = positions.get(pos2);
           for(int idx=0;idx<posData2.count;idx++) {
             //System.out.println("    idx=" + idx + " cost=" + cost);
-            final int cost = posData.costs[idx];
+            final int cost = posData2.costs[idx];
             if (cost < leastCost) {
               leastCost = cost;
               leastIDX = idx;
diff --git a/modules/analysis/kuromoji/src/test/org/apache/lucene/analysis/kuromoji/TestKuromojiAnalyzer.java b/modules/analysis/kuromoji/src/test/org/apache/lucene/analysis/kuromoji/TestKuromojiAnalyzer.java
index d39cf875bf8..4c667e80e8b 100644
--- a/modules/analysis/kuromoji/src/test/org/apache/lucene/analysis/kuromoji/TestKuromojiAnalyzer.java
+++ b/modules/analysis/kuromoji/src/test/org/apache/lucene/analysis/kuromoji/TestKuromojiAnalyzer.java
@@ -153,4 +153,14 @@ public class TestKuromojiAnalyzer extends BaseTokenStreamTestCase {
                               new Integer(4)
     );
   }
+
+  // LUCENE-3897: this string (found by running all jawiki
+  // XML through KuromojiAnalyzer) caused AIOOBE
+  public void testCuriousString() throws Exception {
+    final String s = "&lt;li&gt;06:26 2004年3月21日 [[利用者:Kzhr|Kzhr]] &quot;お菓子な家族&quot; を削除しました &lt;em&gt;&lt;nowiki&gt;(即時削除: 悪戯。内容: &amp;#39;ＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫＫ&amp;#39;)&lt;/nowiki&gt;&lt;/em&gt;&lt;/li&gt;";
+    final Analyzer a = new KuromojiAnalyzer(TEST_VERSION_CURRENT, null, Mode.SEARCH,
+                                            KuromojiAnalyzer.getDefaultStopSet(),
+                                            KuromojiAnalyzer.getDefaultStopTags());
+    checkAnalysisConsistency(random, a, random.nextBoolean(), s);
+  }
 }