diff --git a/NEWS b/NEWS
index 4fa1a0b3..d7d4b03a 100644
--- a/NEWS
+++ b/NEWS
@@ -13,8 +13,6 @@ What's new in psycopg 2.5.4
   (:ticket:`#228`).
 - Cursors :sql:`WITH HOLD` can be used in autocommit (:ticket:`#229`).
 - Don't ignore silently the `cursor.callproc` argument without a length.
-- Added a few errors missing from `~psycopg2.errorcodes`, defined by
-  PostgreSQL but not documented.
 - Make sure the internal `_psycopg.so` module can be imported stand-alone
   (to allow modules juggling such as the one described in :ticket:`#201`).
 - Fixed memory leak with large objects (regression introduced in 2.5.3).
diff --git a/lib/errorcodes.py b/lib/errorcodes.py
index e004cac5..12c300f6 100644
--- a/lib/errorcodes.py
+++ b/lib/errorcodes.py
@@ -284,10 +284,6 @@ STATEMENT_COMPLETION_UNKNOWN = '40003'
 DEADLOCK_DETECTED = '40P01'
 
 # Class 42 - Syntax Error or Access Rule Violation
-UNDEFINED_PSTATEMENT = '26000'
-UNDEFINED_CURSOR = '34000'
-UNDEFINED_DATABASE = '3D000'
-UNDEFINED_SCHEMA = '3F000'
 SYNTAX_ERROR_OR_ACCESS_RULE_VIOLATION = '42000'
 INSUFFICIENT_PRIVILEGE = '42501'
 SYNTAX_ERROR = '42601'
diff --git a/scripts/make_errorcodes.py b/scripts/make_errorcodes.py
index d6e25337..122e0d56 100755
--- a/scripts/make_errorcodes.py
+++ b/scripts/make_errorcodes.py
@@ -72,15 +72,10 @@ def parse_errors_txt(url):
         m = re.match(r"(.....)\s+(?:E|W|S)\s+ERRCODE_(\S+)(?:\s+(\S+))?$", line)
         if m:
             errcode, macro, spec = m.groups()
-            # error 22008 has 2 macros and 1 def: give priority to the def
-            # as it's the one we used to parse from sgml
+            # skip errcodes without specs as they are not publically visible
             if not spec:
-                if errcode in errors[class_]:
-                    continue
-                errlabel = macro.upper()
-            else:
-                errlabel = spec.upper()
-
+                continue
+            errlabel = spec.upper()
             errors[class_][errcode] = errlabel
             continue