diff --git a/tests/bugs/core_6109_test.py b/tests/bugs/core_6109_test.py
index 7a78772f..132e9b68 100644
--- a/tests/bugs/core_6109_test.py
+++ b/tests/bugs/core_6109_test.py
@@ -7,6 +7,11 @@ TITLE:       Changing FLOAT to a SQL standard compliant FLOAT datatype
 DESCRIPTION:
 JIRA:        CORE-6109
 FBTEST:      bugs.core_6109
+NOTES:
+    [13.12.2023] pzotov
+        Added 'SQLSTATE' in substitutions: runtime error must not be filtered out by '?!(...)' pattern
+        ("negative lookahead assertion", see https://docs.python.org/3/library/re.html#regular-expression-syntax).
+        Added 'combine_output = True' in order to see SQLSTATE if any error occurs.
 """
 
 import pytest
@@ -29,7 +34,7 @@ test_script = """
     select * from test;
 """
 
-act = isql_act('db', test_script, substitutions=[('^((?!(sqltype)).)*$', ''), ('[ \t]+', ' ')])
+act = isql_act('db', test_script, substitutions=[('^((?!(SQLSTATE|sqltype)).)*$', ''), ('[ \t]+', ' ')])
 
 expected_stdout = """
     01: sqltype: 482 FLOAT Nullable scale: 0 subtype: 0 len: 4
@@ -43,5 +48,5 @@ expected_stdout = """
 @pytest.mark.version('>=4.0')
 def test_1(act: Action):
     act.expected_stdout = expected_stdout
-    act.execute()
+    act.execute(combine_output = True)
     assert act.clean_stdout == act.clean_expected_stdout