diff --git a/src/sly/lexer/LexerBuilder.cs b/src/sly/lexer/LexerBuilder.cs
index 560c1b8c..6a05dd67 100644
--- a/src/sly/lexer/LexerBuilder.cs
+++ b/src/sly/lexer/LexerBuilder.cs
@@ -175,7 +175,7 @@ private static BuildResult<ILexer<IN>> Build<IN>(Dictionary<IN, (List<LexemeAttr
                     }
                     else
                     {
-                        result = BuildRegexLexer<IN>(attributes, result);
+                        result = BuildRegexLexer<IN>(attributes, lang, result);
                     }
                 }
                 else if (hasGenericLexemes)
@@ -240,10 +240,15 @@ private static bool IsGenericLexer<IN>(Dictionary<IN, (List<LexemeAttribute> lex
         }
 
 
-        private static BuildResult<ILexer<IN>> BuildRegexLexer<IN>(Dictionary<IN, (List<LexemeAttribute> lexemes,List<LexemeLabelAttribute> labels)> attributes,
+        private static BuildResult<ILexer<IN>> BuildRegexLexer<IN>(
+            Dictionary<IN, (List<LexemeAttribute> lexemes, List<LexemeLabelAttribute> labels)> attributes,
+            string lang,
             BuildResult<ILexer<IN>> result) where IN : struct
         {
-            var lexer = new Lexer<IN>();
+            var lexer = new Lexer<IN>()
+            {
+                I18n = lang
+            };
             foreach (var pair in attributes)
             {
                 var tokenID = pair.Key;
diff --git a/tests/ParserTests/ErrorTests.cs b/tests/ParserTests/ErrorTests.cs
index 880bed75..c0a82f96 100644
--- a/tests/ParserTests/ErrorTests.cs
+++ b/tests/ParserTests/ErrorTests.cs
@@ -110,7 +110,7 @@ public void TestLexicalError()
         {
             var exprParser = new ExpressionParser();
 
-            var builder = new ParserBuilder<ExpressionToken, int>();
+            var builder = new ParserBuilder<ExpressionToken, int>("en");
             var Parser = builder.BuildParser(exprParser, ParserType.LL_RECURSIVE_DESCENT, "root").Result;
             var r = Parser.Parse("2 @ 2");
             Check.That(r.IsError).IsTrue();
@@ -120,6 +120,7 @@ public void TestLexicalError()
             Check.That(error.Line).IsEqualTo(1);
             Check.That(error.Column).IsEqualTo(3);
             Check.That(error.UnexpectedChar).IsEqualTo('@');
+            Check.That(error.ErrorMessage).IsEqualTo("Lexical Error, line 1, column 3 : Unrecognized symbol '@' (64)");
         }
     }
 }
\ No newline at end of file