Index: modules/block/block.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/block/block.module,v
retrieving revision 1.251
diff -u -r1.251 block.module
--- modules/block/block.module	31 Jan 2007 15:49:22 -0000	1.251
+++ modules/block/block.module	14 Mar 2007 19:20:50 -0000
@@ -146,6 +146,8 @@
 
   init_theme();
 
+  db_lock_table('blocks');
+  
   $result = db_query("SELECT * FROM {blocks} WHERE theme = '%s'", $theme_key);
   while ($old_block = db_fetch_object($result)) {
     $old_blocks[$old_block->module][$old_block->delta] = $old_block;
@@ -185,7 +187,6 @@
     }
   }
 
-  db_lock_table('blocks');
   // Remove all blocks from table.
   db_query("DELETE FROM {blocks} WHERE theme = '%s'", $theme_key);