diff --git a/components/jvcllaz/run/JvPascalInterpreter/JvInterpreterFm.pas b/components/jvcllaz/run/JvPascalInterpreter/JvInterpreterFm.pas
index 8423d0471..1962c161a 100644
--- a/components/jvcllaz/run/JvPascalInterpreter/JvInterpreterFm.pas
+++ b/components/jvcllaz/run/JvPascalInterpreter/JvInterpreterFm.pas
@@ -160,13 +160,20 @@ uses
 type
   TJvInterpreterReader = class(TReader)
   protected
-    function FindMethod(Root: TComponent; const MethodName: string): Pointer;
-      override;
+    {$IF FPC_FULLVERSION >= 30301}
+    function FindMethod(Root: TComponent; const MethodName: RawByteString): CodePointer; override;
+    {$ELSE}
+    function FindMethod(Root: TComponent; const MethodName: string): Pointer; override;
+    {$ENDIF}
   end;
 
   TJvInterpreterAdapterAccessProtected = class(TJvInterpreterAdapter);
 
+{$IF FPC_FULLVERSION >= 30301}
+function TJvInterpreterReader.FindMethod(Root: TComponent; const MethodName: RawByteString): CodePointer;
+{$ELSE}
 function TJvInterpreterReader.FindMethod(Root: TComponent; const MethodName: string): Pointer;
+{$ENDIF}
 var
   Len: Integer;
 begin