diff --git a/CHANGELOG b/CHANGELOG
index ca6130a..3fbfe7b 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,5 @@
+* 0.4.9
+	- Accept string message format for message signing
 * 0.4.8
 	- Fix server crash on sign request for unknown key
 * 0.4.7
diff --git a/crypto_dev_signer/runnable/signer.py b/crypto_dev_signer/runnable/signer.py
index ce4c07c..41e826b 100755
--- a/crypto_dev_signer/runnable/signer.py
+++ b/crypto_dev_signer/runnable/signer.py
@@ -117,7 +117,10 @@ def eth_signTransaction(tx):
 
 def eth_sign(address, message):
     logg.debug('got message {} to sign'.format(p[0]))
-    return signer.signEthereumMessage(address, message)
+    message_type = type(message).__name__
+    if message_type != 'str':
+        raise ValueError('invalid message format, must be {}, not {}'.format(message_type))
+    return signer.signEthereumMessage(address, message.encode('utf-8'))
 
 
 methods = {
diff --git a/setup.py b/setup.py
index 97cf21b..d256851 100644
--- a/setup.py
+++ b/setup.py
@@ -24,7 +24,7 @@ f.close()
 
 setup(
         name="crypto-dev-signer",
-        version="0.4.8",
+        version="0.4.9",
         description="A signer and keystore daemon and library for cryptocurrency software development",
         author="Louis Holbrook",
         author_email="dev@holbrook.no",