Index: src/test/org/apache/lucene/search/TestSimpleExplanations.java
===================================================================
--- src/test/org/apache/lucene/search/TestSimpleExplanations.java	(revision 1073982)
+++ src/test/org/apache/lucene/search/TestSimpleExplanations.java	(working copy)
@@ -289,4 +289,62 @@
     qtest(q, new int[] { 0,3 });
     
   }
+
+  /* BQ of TQ: using alt so some fields have zero boost and some don't */
+  
+  public void testMultiFieldBQ1() throws Exception {
+    qtest("+w1 +alt:w2", new int[] { 0,1,2,3 });
+  }
+  public void testMultiFieldBQ2() throws Exception {
+    qtest("+yy +alt:w3", new int[] { 2,3 });
+  }
+  public void testMultiFieldBQ3() throws Exception {
+    qtest("yy +alt:w3", new int[] { 0,1,2,3 });
+  }
+  public void testMultiFieldBQ4() throws Exception {
+    qtest("w1 (-xx alt:w2)", new int[] { 0,1,2,3 });
+  }
+  public void testMultiFieldBQ5() throws Exception {
+    qtest("w1 (+alt:qq alt:w2)", new int[] { 0,1,2,3 });
+  }
+  public void testMultiFieldBQ6() throws Exception {
+    qtest("w1 -(-alt:qq alt:w5)", new int[] { 1,2,3 });
+  }
+  public void testMultiFieldBQ7() throws Exception {
+    qtest("+w1 +(alt:qq (alt:xx -alt:w2) (+alt:w3 +alt:w4))", new int[] { 0 });
+  }
+  public void testMultiFieldBQ8() throws Exception {
+    qtest("+alt:w1 (qq (alt:xx -w2) (+alt:w3 +w4))", new int[] { 0,1,2,3 });
+  }
+  public void testMultiFieldBQ9() throws Exception {
+    qtest("+w1 (alt:qq (-xx w2) -(+alt:w3 +w4))", new int[] { 0,1,2,3 });
+  }
+  public void testMultiFieldBQ10() throws Exception {
+    qtest("+w1 +(alt:qq (-xx alt:w2) -(+alt:w3 +w4))", new int[] { 1 });
+  }
+
+  /* BQ of PQ: using alt so some fields have zero boost and some don't */
+  
+  public void testMultiFieldBQofPQ1() throws Exception {
+    qtest("\"w1 w2\" alt:\"w1 w2\"", new int[] { 0 });
+  }
+  public void testMultiFieldBQofPQ2() throws Exception {
+    qtest("\"w1 w3\" alt:\"w1 w3\"", new int[] { 1,3 });
+  }
+  public void testMultiFieldBQofPQ3() throws Exception {
+    qtest("\"w1 w2\"~1 alt:\"w1 w2\"~1", new int[] { 0,1,2 });
+  }
+  public void testMultiFieldBQofPQ4() throws Exception {
+    qtest("\"w2 w3\"~1 alt:\"w2 w3\"~1", new int[] { 0,1,2,3 });
+  }
+  public void testMultiFieldBQofPQ5() throws Exception {
+    qtest("\"w3 w2\"~1 alt:\"w3 w2\"~1", new int[] { 1,3 });
+  }
+  public void testMultiFieldBQofPQ6() throws Exception {
+    qtest("\"w3 w2\"~2 alt:\"w3 w2\"~2", new int[] { 0,1,3 });
+  }
+  public void testMultiFieldBQofPQ7() throws Exception {
+    qtest("\"w3 w2\"~3 alt:\"w3 w2\"~3", new int[] { 0,1,2,3 });
+  }
+
 }
Index: src/test/org/apache/lucene/search/TestExplanations.java
===================================================================
--- src/test/org/apache/lucene/search/TestExplanations.java	(revision 1073982)
+++ src/test/org/apache/lucene/search/TestExplanations.java	(working copy)
@@ -52,7 +52,10 @@
   protected Directory directory;
   
   public static final String KEY = "KEY";
+  // boost on this field is the same as the iterator for the doc
   public static final String FIELD = "field";
+  // same contents, but no field boost
+  public static final String ALTFIELD = "alt";
   public static final QueryParser qp =
     new QueryParser(TEST_VERSION_CURRENT, FIELD, new MockAnalyzer());
 
@@ -72,7 +75,10 @@
     for (int i = 0; i < docFields.length; i++) {
       Document doc = new Document();
       doc.add(newField(KEY, ""+i, Field.Store.NO, Field.Index.NOT_ANALYZED));
-      doc.add(newField(FIELD, docFields[i], Field.Store.NO, Field.Index.ANALYZED));
+      Field f = newField(FIELD, docFields[i], Field.Store.NO, Field.Index.ANALYZED);
+      f.setBoost(i);
+      doc.add(f);
+      doc.add(newField(ALTFIELD, docFields[i], Field.Store.NO, Field.Index.ANALYZED));
       writer.addDocument(doc);
     }
     reader = writer.getReader();