diff --git a/include/class.organization.php b/include/class.organization.php
index 3342289557c1077eeabebe7dc86e21c9f9a4d679..e1e3f44350bad64c26dcde031da2a1a2844b3eb8 100644
--- a/include/class.organization.php
+++ b/include/class.organization.php
@@ -159,7 +159,14 @@ class Organization extends OrganizationModel {
 
     function isMappedToDomain($domain) {
         foreach (explode(',', $this->domain) as $d) {
-            if (strcasecmp($domain, trim($d)) === 0) {
+            $d = trim($d);
+            if ($d[0] == '.') {
+                // Subdomain syntax (.osticket.com accepts all subdomains of
+                // osticket.com)
+                if (strcasecmp(mb_substr($domain, -mb_strlen($d)), $d) === 0)
+                    return true;
+            }
+            elseif (strcasecmp($domain, $d) === 0) {
                 return true;
             }
         }