diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 56a80e6..20f3909 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-    ".": "5.4.8"
+    ".": "5.4.9"
 }
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 38aaabe..ea4d9de 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Changelog
 
+## [5.4.9](https://github.com/zone-eu/mailsplit/compare/v5.4.8...v5.4.9) (2026-04-09)
+
+
+### Bug Fixes
+
+* ZMS-47: Fix utf-8 header round-trip in Headers.add() ([#46](https://github.com/zone-eu/mailsplit/issues/46)) ([629928b](https://github.com/zone-eu/mailsplit/commit/629928b1eb22f4ae2753b13eb1df633460b994b2))
+
 ## [5.4.8](https://github.com/zone-eu/mailsplit/compare/v5.4.7...v5.4.8) (2025-12-08)
 
 
diff --git a/package-lock.json b/package-lock.json
index c3c83b4..cd42312 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
     "name": "@zone-eu/mailsplit",
-    "version": "5.4.8",
+    "version": "5.4.9",
     "lockfileVersion": 3,
     "requires": true,
     "packages": {
         "": {
             "name": "@zone-eu/mailsplit",
-            "version": "5.4.8",
+            "version": "5.4.9",
             "license": "(MIT OR EUPL-1.1+)",
             "dependencies": {
                 "libbase64": "1.3.0",
diff --git a/package.json b/package.json
index 281bcf3..46d6ece 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
     "name": "@zone-eu/mailsplit",
-    "version": "5.4.8",
+    "version": "5.4.9",
     "description": "Split email messages into an object stream",
     "main": "index.js",
     "directories": {