diff --git a/src/packet/signature.js b/src/packet/signature.js
index 1b443bc6..8316adb2 100644
--- a/src/packet/signature.js
+++ b/src/packet/signature.js
@@ -572,7 +572,7 @@ Signature.prototype.toSign = function (type, data) {
   switch (type) {
     case t.binary:
       if (data.text !== null) {
-        return util.str_to_Uint8Array(data.getText(true));
+        return util.encode_utf8(data.getText(true));
       }
       return data.getBytes(true);
 
diff --git a/test/general/signature.js b/test/general/signature.js
index ef9f013a..d3a97c9a 100644
--- a/test/general/signature.js
+++ b/test/general/signature.js
@@ -997,7 +997,7 @@ hkJiXopCSWKSlQInL1devkJJUWJmTmZeugJYlpdLAagQJM0JpsCqIQZwKgAA
 
   it('Should verify cleartext message correctly when using a detached binary signature and text literal data', async function () {
     const plaintext = 'short message\nnext line \n한국어/조선말';
-    const plaintextArray = openpgp.util.str_to_Uint8Array(plaintext);
+    const plaintextArray = openpgp.util.encode_utf8(plaintext);
     const pubKey = (await openpgp.key.readArmored(pub_key_arm2)).keys[0];
     const privKey = (await openpgp.key.readArmored(priv_key_arm2)).keys[0];
     await privKey.decrypt('hello world');