diff --git a/migrations/20160528090040-mailboxes-import-existing-users.js b/migrations/20160528090040-mailboxes-import-existing-users.js
new file mode 100644
index 000000000..ed7602412
--- /dev/null
+++ b/migrations/20160528090040-mailboxes-import-existing-users.js
@@ -0,0 +1,23 @@
+var dbm = global.dbm || require('db-migrate');
+var type = dbm.dataType;
+
+// imports mailbox entries for existing users
+exports.up = function(db, callback) {
+    async.series([
+        db.runSql.bind(db, 'START TRANSACTION;'),
+        function addUserMailboxes(done) {
+            db.all('SELECT username FROM users', function (error, results) {
+                if (error) return done(error);
+
+                async.eachSeries(results, function (r, next) {
+                    db.runSql('INSERT INTO mailboxes (name) VALUES (?)', [ r.username ], next);
+                }, done);
+            });
+        },
+       db.runSql.bind(db, 'COMMIT')
+    ], callback);
+};
+
+exports.down = function(db, callback) {
+  callback();
+};
diff --git a/migrations/20160528090040-mailboxes-import-existing.js b/migrations/20160528090040-mailboxes-import-existing.js
deleted file mode 100644
index ab64173bd..000000000
--- a/migrations/20160528090040-mailboxes-import-existing.js
+++ /dev/null
@@ -1,38 +0,0 @@
-var dbm = global.dbm || require('db-migrate');
-var type = dbm.dataType;
-
-// imports mailbox entries for existing users and apps
-exports.up = function(db, callback) {
-    async.series([
-        db.runSql.bind(db, 'START TRANSACTION;'),
-        function addUserMailboxes(done) {
-            db.all('SELECT username FROM users', function (error, results) {
-                if (error) return done(error);
-
-                console.dir(results);
-
-                async.eachSeries(results, function (r, next) {
-                    db.runSql('INSERT INTO mailboxes (name) VALUES (?)', [ r.username ], next);
-                }, done);
-            });
-        },
-        function addAppMailboxes(done) {
-            db.all('SELECT location, manifestJson FROM apps', function (error, results) {
-                if (error) return done(error);
-
-                console.dir(results);
-
-                async.eachSeries(results, function (r, next) {
-                    var app = { location: r.location, manifest: JSON.parse(r.manifestJson) };
-                    var from = (app.location ? app.location : app.manifest.title.replace(/[^a-zA-Z0-9]/, '')) + '.app';
-                    db.runSql('INSERT INTO mailboxes (name) VALUES (?)', [ from ], next);
-                }, done);
-            });
-        },
-        db.runSql.bind(db, 'COMMIT')
-    ], callback);
-};
-
-exports.down = function(db, callback) {
-  callback();
-};
diff --git a/src/mailboxes.js b/src/mailboxes.js
index 1c404956c..d3c19becd 100644
--- a/src/mailboxes.js
+++ b/src/mailboxes.js
@@ -55,6 +55,8 @@ function validateName(name) {
 
     if (/[^a-zA-Z0-9.]/.test(name)) return new MailboxError(MailboxError.BAD_NAME, 'Name can only contain alphanumerals and dot');
 
+    if (name.indexOf('.app') !== -1) return new UserError(UserError.BAD_USERNAME, 'Alias pattern is reserved for apps');
+
     return null;
 }
 
diff --git a/src/user.js b/src/user.js
index 22133294e..59076d8fa 100644
--- a/src/user.js
+++ b/src/user.js
@@ -95,6 +95,7 @@ function validateUsername(username) {
     // +/- can be tricky in emails
     if (/[^a-zA-Z0-9.]/.test(username)) return new UserError(UserError.BAD_USERNAME, 'Username can only contain alphanumerals and dot');
 
+    // app emails are sent using the .app suffix
     if (username.indexOf('.app') !== -1) return new UserError(UserError.BAD_USERNAME, 'Username pattern is reserved for apps');
 
     return null;