diff --git a/psycopg/connection_type.c b/psycopg/connection_type.c
index efbe9e62..8e6758ac 100644
--- a/psycopg/connection_type.c
+++ b/psycopg/connection_type.c
@@ -74,8 +74,8 @@ psyco_conn_cursor(connectionObject *self, PyObject *args, PyObject *keywds)
         return NULL;
     }
 
-    if (name != NULL && self->async) {
-        PyErr_SetString(OperationalError,
+    if (name != NULL && self->async == 1) {
+        PyErr_SetString(ProgrammingError,
                         "asynchronous connections "
                         "cannot produce named cursors");
         return NULL;