Index: lucene/suggest/src/test/org/apache/lucene/search/suggest/fst/WFSTCompletionTest.java
===================================================================
--- lucene/suggest/src/test/org/apache/lucene/search/suggest/fst/WFSTCompletionTest.java	(revision 1405545)
+++ lucene/suggest/src/test/org/apache/lucene/search/suggest/fst/WFSTCompletionTest.java	(working copy)
@@ -22,6 +22,7 @@
 import org.apache.lucene.search.suggest.Lookup.LookupResult;
 import org.apache.lucene.search.suggest.TermFreq;
 import org.apache.lucene.search.suggest.TermFreqArrayIterator;
+import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.LuceneTestCase;
 import org.apache.lucene.util._TestUtil;
 
@@ -194,4 +195,18 @@
       }
     }
   }
+
+  public void test0ByteKeys() throws Exception {
+    BytesRef key1 = new BytesRef(4);
+    key1.length = 4;
+    BytesRef key2 = new BytesRef(3);
+    key1.length = 3;
+
+    WFSTCompletionLookup suggester = new WFSTCompletionLookup(false);
+
+    suggester.build(new TermFreqArrayIterator(new TermFreq[] {
+          new TermFreq(key1, 50),
+          new TermFreq(key2, 50),
+        }));
+  }
 }
Index: lucene/suggest/src/test/org/apache/lucene/search/suggest/analyzing/AnalyzingSuggesterTest.java
===================================================================
--- lucene/suggest/src/test/org/apache/lucene/search/suggest/analyzing/AnalyzingSuggesterTest.java	(revision 1405545)
+++ lucene/suggest/src/test/org/apache/lucene/search/suggest/analyzing/AnalyzingSuggesterTest.java	(working copy)
@@ -983,4 +983,49 @@
     assertEquals("b", results.get(1).key);
     assertEquals(5, results.get(1).value);
   }
+
+  public void test0ByteKeys() throws Exception {
+    final Analyzer a = new Analyzer() {
+        @Override
+        protected TokenStreamComponents createComponents(String fieldName, Reader reader) {
+          Tokenizer tokenizer = new MockTokenizer(reader, MockTokenizer.SIMPLE, true);
+        
+          return new TokenStreamComponents(tokenizer) {
+            int tokenStreamCounter = 0;
+            final TokenStream[] tokenStreams = new TokenStream[] {
+              new CannedBinaryTokenStream(new BinaryToken[] {
+                  token(new BytesRef(new byte[] {0x0, 0x0, 0x0})),
+                }),
+              new CannedBinaryTokenStream(new BinaryToken[] {
+                  token(new BytesRef(new byte[] {0x0, 0x0})),
+                }),
+              new CannedBinaryTokenStream(new BinaryToken[] {
+                  token(new BytesRef(new byte[] {0x0, 0x0, 0x0})),
+                }),
+              new CannedBinaryTokenStream(new BinaryToken[] {
+                  token(new BytesRef(new byte[] {0x0, 0x0})),
+                }),
+            };
+
+            @Override
+            public TokenStream getTokenStream() {
+              TokenStream result = tokenStreams[tokenStreamCounter];
+              tokenStreamCounter++;
+              return result;
+            }
+         
+            @Override
+            protected void setReader(final Reader reader) throws IOException {
+            }
+          };
+        }
+      };
+
+    AnalyzingSuggester suggester = new AnalyzingSuggester(a, a, 0, 256, -1);
+
+    suggester.build(new TermFreqArrayIterator(new TermFreq[] {
+          new TermFreq("a a", 50),
+          new TermFreq("a b", 50),
+        }));
+  }
 }