diff --git a/server/conf/sieve_filter.master b/server/conf/sieve_filter.master
index 51d8eeee149193a99fc3d0a7d51f5d17208d0c93..dd2dfb96473667b849fb98527d1551263d043b3a 100644
--- a/server/conf/sieve_filter.master
+++ b/server/conf/sieve_filter.master
@@ -17,7 +17,7 @@ if anyof (header :contains "X-Spam-Flag" "YES", header :contains "X-Spam" "Yes",
 <tmpl_if name="cc">
 # Send a copy of email to
 <tmpl_loop name="ccloop">
-redirect "<tmpl_var name='address'>";
+redirect :copy "<tmpl_var name='address'>";
 </tmpl_loop>
 </tmpl_if>