Index: FieldSortedHitQueue.java
===================================================================
--- FieldSortedHitQueue.java	(revision 654583)
+++ FieldSortedHitQueue.java	(working copy)
@@ -53,7 +53,12 @@
     this.fields = new SortField[n];
     for (int i=0; i<n; ++i) {
       String fieldname = fields[i].getField();
-      comparators[i] = getCachedComparator (reader, fieldname, fields[i].getType(), fields[i].getLocale(), fields[i].getFactory());
+
+      if(fields[i].getFactory() instanceof SortComparatorSourceUncacheable) { // no caching to avoid memory leak
+        comparators[i] = getComparator (reader, fieldname, fields[i].getType(), fields[i].getLocale(), fields[i].getFactory());
+      } else {
+        comparators[i] = getCachedComparator (reader, fieldname, fields[i].getType(), fields[i].getLocale(), fields[i].getFactory());
+      }
       
       if (comparators[i].sortType() == SortField.STRING) {
     	  this.fields[i] = new SortField (fieldname, fields[i].getLocale(), fields[i].getReverse());
@@ -157,7 +162,18 @@
   SortField[] getFields() {
     return fields;
   }
-  
+
+  static ScoreDocComparator getComparator (IndexReader reader, String field, int type, Locale locale, SortComparatorSource factory)
+    throws IOException {
+      if (type == SortField.DOC) return ScoreDocComparator.INDEXORDER;
+      if (type == SortField.SCORE) return ScoreDocComparator.RELEVANCE;
+      FieldCacheImpl.Entry entry = (factory != null)
+        ? new FieldCacheImpl.Entry (field, factory)
+        : new FieldCacheImpl.Entry (field, type, locale);
+      return (ScoreDocComparator)Comparators.createValue(reader, entry);
+    }
+
+
   static ScoreDocComparator getCachedComparator (IndexReader reader, String field, int type, Locale locale, SortComparatorSource factory)
   throws IOException {
     if (type == SortField.DOC) return ScoreDocComparator.INDEXORDER;
Index: SortComparatorSourceUncacheable.java
===================================================================
--- SortComparatorSourceUncacheable.java	(revision 0)
+++ SortComparatorSourceUncacheable.java	(revision 0)
@@ -0,0 +1,16 @@
+package org.apache.lucene.search;
+
+import org.apache.lucene.index.IndexReader;
+import java.io.IOException;
+import java.io.Serializable;
+
+/**
+ * Expert: returns a comparator for sorting ScoreDocs.
+ *
+ * <p>Created: May 23, 2008 3:49:28 PM
+ *
+ * @version $Id: SortComparatorSourceUncacheable.java 564236 2008-05-23 15:21:19Z EthanT $
+ * @since   1.6
+ */
+public interface SortComparatorSourceUncacheable extends Serializable {
+}