Index: src/resolve.c
==================================================================
--- src/resolve.c
+++ src/resolve.c
@@ -992,13 +992,15 @@
         pNew->flags |= EP_IntValue;
         pNew->u.iValue = iCol;
         if( pItem->pExpr==pE ){
           pItem->pExpr = pNew;
         }else{
-          assert( pItem->pExpr->op==TK_COLLATE );
-          assert( pItem->pExpr->pLeft==pE );
-          pItem->pExpr->pLeft = pNew;
+          Expr *pParent = pItem->pExpr;
+          assert( pParent->op==TK_COLLATE );
+          while( pParent->pLeft->op==TK_COLLATE ) pParent = pParent->pLeft;
+          assert( pParent->pLeft==pE );
+          pParent->pLeft = pNew;
         }
         sqlite3ExprDelete(db, pE);
         pItem->u.x.iOrderByCol = (u16)iCol;
         pItem->done = 1;
       }else{

Index: test/collate1.test
==================================================================
--- test/collate1.test
+++ test/collate1.test
@@ -383,8 +383,22 @@
   INSERT INTO c1 VALUES(3, 'wxz');
   INSERT INTO c1 VALUES(4, 'WXY');
   SELECT x, y FROM c1 ORDER BY y COLLATE """""""";
 } {2 abb 1 ABC 4 WXY 3 wxz}
 
-finish_test
+# 2015-04-15:  Nested COLLATE operators
+#
+do_execsql_test 7.0 {
+   SELECT 'abc' UNION ALL SELECT 'DEF'
+    ORDER BY 1 COLLATE nocase COLLATE nocase COLLATE nocase COLLATE nocase;
+} {abc DEF}
+do_execsql_test 7.1 {
+   SELECT 'abc' UNION ALL SELECT 'DEF'
+    ORDER BY 1 COLLATE nocase COLLATE nocase COLLATE nocase COLLATE binary;
+} {DEF abc}
+do_execsql_test 7.2 {
+   SELECT 'abc' UNION ALL SELECT 'DEF'
+    ORDER BY 1 COLLATE binary COLLATE binary COLLATE binary COLLATE nocase;
+} {abc DEF}
 
 
+finish_test