diff --git a/CHANGELOG b/CHANGELOG
index ab6edb96ff..63f572049d 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,5 @@
+* Use bigdecimal tag for XML-RPC
+
 Version 6.0.0 - 2021-05-03
 * Bug fixes (see mercurial logs for details)
 * Add support for Python 3.9
diff --git a/proteus/config.py b/proteus/config.py
index e2244eb606..efadc77126 100644
--- a/proteus/config.py
+++ b/proteus/config.py
@@ -15,10 +15,9 @@ __all__ = ['set_trytond', 'set_xmlrpc', 'get_config']
 
 
 def dump_decimal(self, value, write):
-    value = {'__class__': 'Decimal',
-        'decimal': str(value),
-        }
-    self.dump_struct(value, write)
+    write('<value><bigdecimal>')
+    write(str(Decimal(value)))
+    write('</bigdecimal></value>')
 
 
 def dump_date(self, value, write):