diff --git a/src/addons.js b/src/addons.js
index b427b0e42..4ad49a6a4 100644
--- a/src/addons.js
+++ b/src/addons.js
@@ -366,7 +366,7 @@ function setupSendMail(app, options, callback) {
             { name: 'MAIL_SMTP_SERVER', value: 'mail' },
             { name: 'MAIL_SMTP_PORT', value: '2525' },
             { name: 'MAIL_SMTPS_PORT', value: '4650' },
-            { name: 'MAIL_SMTP_USERNAME', value: mailbox.name },
+            { name: 'MAIL_SMTP_USERNAME', value: mailbox.name + '@' + app.domain },
             { name: 'MAIL_SMTP_PASSWORD', value: password },
             { name: 'MAIL_FROM', value: mailbox.name + '@' + app.domain },
             { name: 'MAIL_DOMAIN', value: app.domain }
@@ -402,7 +402,7 @@ function setupRecvMail(app, options, callback) {
         var env = [
             { name: 'MAIL_IMAP_SERVER', value: 'mail' },
             { name: 'MAIL_IMAP_PORT', value: '9993' },
-            { name: 'MAIL_IMAP_USERNAME', value: mailbox.name },
+            { name: 'MAIL_IMAP_USERNAME', value: mailbox.name + '@' + app.domain },
             { name: 'MAIL_IMAP_PASSWORD', value: password },
             { name: 'MAIL_TO', value: mailbox.name + '@' + app.domain },
             { name: 'MAIL_DOMAIN', value: app.domain }
diff --git a/src/infra_version.js b/src/infra_version.js
index cf459d4ec..5a82bfd7c 100644
--- a/src/infra_version.js
+++ b/src/infra_version.js
@@ -7,7 +7,7 @@
 exports = module.exports = {
     // a major version makes all apps restore from backup. #451 must be fixed before we do this.
     // a minor version makes all apps re-configure themselves
-    'version': '48.8.0',
+    'version': '48.9.0',
 
     'baseImages': [ 'cloudron/base:0.10.0' ],