diff -ur mysql-5.5.18.orig/sql-common/client.c mysql-5.5.18/sql-common/client.c
--- mysql-5.5.18.orig/sql-common/client.c	2011-11-21 18:06:36.895327989 +0100
+++ mysql-5.5.18/sql-common/client.c	2011-11-21 18:07:44.511213214 +0100
@@ -3668,8 +3668,9 @@
   LIST *element= mysql->stmts;
   LIST *pruned_list= 0;
 
-  for (; element; element= element->next)
+  while (element)
   {
+    LIST *next= element->next;
     MYSQL_STMT *stmt= (MYSQL_STMT *) element->data;
     if (stmt->state != MYSQL_STMT_INIT_DONE)
     {
@@ -3680,8 +3681,11 @@
     }
     else
     {
+      element->prev= 0;
+      element->next= 0;
       pruned_list= list_add(pruned_list, element);
     }
+    element= next;
   }
 
   mysql->stmts= pruned_list;