diff --git a/source/Compiler.ob07 b/source/Compiler.ob07
index 6ed5efd..21fdacd 100644
--- a/source/Compiler.ob07
+++ b/source/Compiler.ob07
@@ -1,7 +1,7 @@
 (*
     BSD 2-Clause License
 
-    Copyright (c) 2018-2023, Anton Krotov
+    Copyright (c) 2018-2023, 2025 Anton Krotov
     All rights reserved.
 *)
 
@@ -222,7 +222,7 @@ BEGIN
     C.Ln;
     C.String("Akron Oberon Compiler v"); C.Int(UTILS.vMajor); C.String("."); C.Int2(UTILS.vMinor);
         C.String(" ("); C.Int(UTILS.bit_depth); C.StringLn("-bit) " + UTILS.Date);
-    C.StringLn("Copyright (c) 2018-2023, Anton Krotov");
+    C.StringLn("Copyright (c) 2018-2025, Anton Krotov");
 
     IF inname = "" THEN
         C.Ln;
diff --git a/source/PARS.ob07 b/source/PARS.ob07
index 17d1ab3..212032d 100644
--- a/source/PARS.ob07
+++ b/source/PARS.ob07
@@ -1,7 +1,7 @@
 (*
     BSD 2-Clause License
 
-    Copyright (c) 2018-2022, Anton Krotov
+    Copyright (c) 2018-2022, 2025 Anton Krotov
     All rights reserved.
 *)
 
@@ -391,7 +391,7 @@ BEGIN
     parser.constexp := TRUE;
     parser.expression(parser, e);
     parser.constexp := FALSE;
-    check(e.obj = eCONST, pos, 62);
+    check((e.obj = eCONST) & (e._type # PROG.program.stTypes.tNIL), pos, 62);
     v := e.value
 END ConstExpression;
 
diff --git a/source/UTILS.ob07 b/source/UTILS.ob07
index e6201ec..b56cb7a 100644
--- a/source/UTILS.ob07
+++ b/source/UTILS.ob07
@@ -1,7 +1,7 @@
 (*
     BSD 2-Clause License
 
-    Copyright (c) 2018-2023, Anton Krotov
+    Copyright (c) 2018-2023, 2025 Anton Krotov
     All rights reserved.
 *)
 
@@ -23,8 +23,8 @@ CONST
     max32* =  2147483647;
 
     vMajor* = 1;
-    vMinor* = 66;
-    Date* = "10-feb-2023";
+    vMinor* = 67;
+    Date* = "04-jun-2025";
 
     FILE_EXT* = ".ob07";
     RTL_NAME* = "RTL";