Index: contrib/misc/src/java/org/apache/lucene/index/IndexSplitter.java
===================================================================
--- contrib/misc/src/java/org/apache/lucene/index/IndexSplitter.java	(revision 1042904)
+++ contrib/misc/src/java/org/apache/lucene/index/IndexSplitter.java	(working copy)
@@ -134,6 +134,7 @@
       int idx = getIdx(n);
       infos.remove(idx);
     }
+    infos.changed();
     infos.commit(fsDir);
   }
 
@@ -152,6 +153,7 @@
         copyFile(srcFile, destFile);
       }
     }
+    destInfos.changed();
     destInfos.commit(destFSDir);
     // System.out.println("destDir:"+destDir.getAbsolutePath());
   }
Index: src/java/org/apache/lucene/index/CheckIndex.java
===================================================================
--- src/java/org/apache/lucene/index/CheckIndex.java	(revision 1042904)
+++ src/java/org/apache/lucene/index/CheckIndex.java	(working copy)
@@ -879,6 +879,7 @@
   public void fixIndex(Status result) throws IOException {
     if (result.partial)
       throw new IllegalArgumentException("can only fix an index that was fully checked (this status checked a subset of segments)");
+    result.newSegments.changed();
     result.newSegments.commit(result.dir);
   }
 
Index: src/java/org/apache/lucene/index/DirectoryReader.java
===================================================================
--- src/java/org/apache/lucene/index/DirectoryReader.java	(revision 1042904)
+++ src/java/org/apache/lucene/index/DirectoryReader.java	(working copy)
@@ -770,6 +770,7 @@
                                                       deletionPolicy == null ? new KeepOnlyLastCommitDeletionPolicy() : deletionPolicy,
                                                       segmentInfos, null, null, codecs);
       segmentInfos.updateGeneration(deleter.getLastSegmentInfos());
+      segmentInfos.changed();
 
       // Checkpoint the state we are about to change, in
       // case we have to roll back:
@@ -782,7 +783,6 @@
 
         // Sync all files we just wrote
         directory.sync(segmentInfos.files(directory, false));
-
         segmentInfos.commit(directory);
         success = true;
       } finally {
Index: src/java/org/apache/lucene/index/IndexWriter.java
===================================================================
--- src/java/org/apache/lucene/index/IndexWriter.java	(revision 1042904)
+++ src/java/org/apache/lucene/index/IndexWriter.java	(working copy)
@@ -741,6 +741,7 @@
         // Record that we have a change (zero out all
         // segments) pending:
         changeCount++;
+        segmentInfos.changed();
       } else {
         segmentInfos.read(directory, codecs);
 
@@ -757,6 +758,7 @@
           oldInfos.read(directory, commit.getSegmentsFileName(), codecs);
           segmentInfos.replace(oldInfos);
           changeCount++;
+          segmentInfos.changed();
           if (infoStream != null)
             message("init: loaded commit \"" + commit.getSegmentsFileName() + "\"");
         }
@@ -774,12 +776,14 @@
                                      conf.getIndexDeletionPolicy(),
                                      segmentInfos, infoStream, docWriter, codecs);
 
-      if (deleter.startingCommitDeleted)
+      if (deleter.startingCommitDeleted) {
         // Deletion policy deleted the "head" commit point.
         // We have to mark ourself as changed so that if we
         // are closed w/o any further changes we write a new
         // segments_N file.
         changeCount++;
+        segmentInfos.changed();
+      }
 
       docWriter.setMaxBufferedDeleteTerms(conf.getMaxBufferedDeleteTerms());
       docWriter.setRAMBufferSizeMB(conf.getRAMBufferSizeMB());
@@ -1537,6 +1541,7 @@
       // name that was previously returned which can cause
       // problems at least with ConcurrentMergeScheduler.
       changeCount++;
+      segmentInfos.changed();
       return "_" + Integer.toString(segmentInfos.counter++, Character.MAX_RADIX);
     }
   }
@@ -2038,6 +2043,7 @@
 
       // Mark that the index has changed
       ++changeCount;
+      segmentInfos.changed();
     } catch (OutOfMemoryError oom) {
       handleOOM(oom, "deleteAll");
     } finally {
@@ -2119,6 +2125,7 @@
    */
   private synchronized void checkpoint() throws IOException {
     changeCount++;
+    segmentInfos.changed();
     deleter.checkpoint(segmentInfos, false);
   }
 
@@ -3686,6 +3693,7 @@
             }
             toSync.remove(toSync.size()-1);
             changeCount++;
+            segmentInfos.changed();
           }
         }
         assert filesExist(toSync);
Index: src/java/org/apache/lucene/index/SegmentInfos.java
===================================================================
--- src/java/org/apache/lucene/index/SegmentInfos.java	(revision 1042904)
+++ src/java/org/apache/lucene/index/SegmentInfos.java	(working copy)
@@ -696,7 +696,6 @@
   void updateGeneration(SegmentInfos other) {
     lastGeneration = other.lastGeneration;
     generation = other.generation;
-    version = other.version;
   }
 
   final void rollbackCommit(Directory dir) throws IOException {
@@ -811,7 +810,11 @@
   }
 
   /** Writes & syncs to the Directory dir, taking care to
-   *  remove the segments file on exception */
+   *  remove the segments file on exception
+   *  <p>
+   *  Note: {@link #changed()} should be called prior to this
+   *  method if changes have been made to this {@link SegmentInfos}  
+   **/
   final void commit(Directory dir) throws IOException {
     prepareCommit(dir);
     finishCommit(dir);
@@ -862,4 +865,10 @@
     }
     return count;
   }
+
+  /** Call this before committing if changes have been made to the
+   *  segments. */
+  public void changed() {
+    version++;
+  }
 }
Index: src/java/org/apache/lucene/index/codecs/DefaultSegmentInfosWriter.java
===================================================================
--- src/java/org/apache/lucene/index/codecs/DefaultSegmentInfosWriter.java	(revision 1042904)
+++ src/java/org/apache/lucene/index/codecs/DefaultSegmentInfosWriter.java	(working copy)
@@ -51,8 +51,7 @@
           throws IOException {
     IndexOutput out = createOutput(dir, segmentFileName);
     out.writeInt(FORMAT_CURRENT); // write FORMAT
-    out.writeLong(++infos.version); // every write changes
-                                 // the index
+    out.writeLong(infos.version);
     out.writeInt(infos.counter); // write counter
     out.writeInt(infos.size()); // write infos
     for (SegmentInfo si : infos) {