Index: forgon-core/src/main/java/com/forgon/treenode/service/THTreeNodeManagerImpl.java
===================================================================
diff -u -r17777 -r26893
--- forgon-core/src/main/java/com/forgon/treenode/service/THTreeNodeManagerImpl.java	(.../THTreeNodeManagerImpl.java)	(revision 17777)
+++ forgon-core/src/main/java/com/forgon/treenode/service/THTreeNodeManagerImpl.java	(.../THTreeNodeManagerImpl.java)	(revision 26893)
@@ -594,8 +594,11 @@
 	@SuppressWarnings("unchecked")
 	public List<THTreeNode> findChildrenByParentId(String subClassName,
 			Long parentId) {
-		String hql = "where po.parent=" + parentId
-				+ " order by sequenceNumber asc";
+		String hql = "where po.parent is null ";
+		if (parentId != null) {
+			hql = "where po.parent=" + parentId;
+		}
+		hql += " order by sequenceNumber asc";
 
 		List<THTreeNode> children = objectDao.findBySql(subClassName, hql);