diff --git a/src/shop/epay.py b/src/shop/epay.py
index 3aef9faa..dba32ba1 100644
--- a/src/shop/epay.py
+++ b/src/shop/epay.py
@@ -24,6 +24,6 @@ def validate_epay_callback(query):
     for key, value in query.items():
         if key != 'hash':
             hashstring += value
-    hash = hashlib.md5(hashstring + settings.EPAY_MD5_SECRET).hexdigest()
+    hash = hashlib.md5((hashstring + settings.EPAY_MD5_SECRET).encode('utf-8')).hexdigest()
     return hash == query['hash']