diff --git a/python-pymilter.changes b/python-pymilter.changes
index 88d5321..e8a0f9f 100644
--- a/python-pymilter.changes
+++ b/python-pymilter.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Wed Jul 30 04:59:43 UTC 2025 - Steve Kowalik <steven.kowalik@suse.com>
+
+- Add patch set-c-standard-17.patch:
+  * Set the C standard to c17 until libmilter is fixed.
+
 -------------------------------------------------------------------
 Tue Jun 10 09:04:00 UTC 2025 - Markéta Machová <mmachova@suse.com>
 
diff --git a/python-pymilter.spec b/python-pymilter.spec
index b150a6a..f4926a2 100644
--- a/python-pymilter.spec
+++ b/python-pymilter.spec
@@ -30,6 +30,8 @@ Source0:        https://github.com/sdgathman/pymilter/archive/pymilter-%{version
 Source1:        tmpfiles-python-pymilter.conf
 # PATCH-FIX-UPSTREAM: https://github.com/sdgathman/pymilter/pull/57
 Patch1:         0001-Remove-calls-to-the-deprecated-method-assertEquals.patch
+# PATCH-FIX-UPSTREAM https://github.com/sdgathman/pymilter/pull/70
+Patch2:         set-c-standard-17.patch
 BuildRequires:  %{python_module bsddb3}
 BuildRequires:  %{python_module devel}
 BuildRequires:  %{python_module pip}
diff --git a/set-c-standard-17.patch b/set-c-standard-17.patch
new file mode 100644
index 0000000..fe94cd0
--- /dev/null
+++ b/set-c-standard-17.patch
@@ -0,0 +1,27 @@
+From 050b3a15bc00a31968cbdcf627692c1eb2ca3219 Mon Sep 17 00:00:00 2001
+From: Sandro <devel@penguinpee.nl>
+Date: Wed, 12 Mar 2025 23:44:55 +0100
+Subject: [PATCH] Set C standard to C17 explicitely
+
+GCC 15 uses C23 by default. But `libmilter` is not compatible, yet.
+This breaks the build as `bool` is a keyword in C23 (issue #68).
+---
+ setup.py | 5 ++++-
+ 1 file changed, 4 insertions(+), 1 deletion(-)
+
+diff --git a/setup.py b/setup.py
+index 958feee..a6fe2a0 100644
+--- a/setup.py
++++ b/setup.py
+@@ -36,7 +36,10 @@
+ 	    # set MAX_ML_REPLY to 1 for sendmail < 8.13
+ 	    define_macros = [ ('MAX_ML_REPLY',32) ],
+             # save lots of debugging time testing rfc2553 compliance
+-            extra_compile_args = [ "-Werror=implicit-function-declaration" ]
++            extra_compile_args = [
++                "-Werror=implicit-function-declaration",
++                "-std=gnu17",
++            ]
+ 	  ),
+ 	],
+ 	keywords = ['sendmail','milter'],