diff --git a/core/nginx/dovecot/login.lua b/core/nginx/dovecot/login.lua
index a93b4b29..442833f1 100644
--- a/core/nginx/dovecot/login.lua
+++ b/core/nginx/dovecot/login.lua
@@ -30,7 +30,8 @@ function auth_passdb_lookup(req)
     auth_request:add_header('Auth-Pass', password)
   end
   auth_request:add_header('Auth-Protocol', req.service)
-  auth_request:add_header('Client-IP', req.remote_ip)
+  local client_ip = urlEncode(req.remote_ip)
+  auth_request:add_header('Client-Ip', client_ip)
   auth_request:add_header('Client-Port', req.remote_port)
   auth_request:add_header('Auth-SSL', req.secured)
   auth_request:add_header('Auth-Method', req.mechanism)