diff --git a/ec2api/wsgi.py b/ec2api/wsgi.py
index 961dae35..3af54e82 100644
--- a/ec2api/wsgi.py
+++ b/ec2api/wsgi.py
@@ -47,6 +47,9 @@ wsgi_opts = [
              'generate log lines. The following values can be formatted '
              'into it: client_ip, date_time, request_line, status_code, '
              'body_length, wall_seconds.'),
+    cfg.StrOpt('ssl_ca_file',
+               help="Path to the CA certificate file that should be used"
+                    "to verify connecting clients."),
     cfg.StrOpt('ssl_cert_file',
                help="SSL certificate of API server"),
     cfg.StrOpt('ssl_key_file',
@@ -157,17 +160,19 @@ class Server(ServiceBase):
 
         if self._use_ssl:
             try:
+                ca_file = CONF.ssl_ca_file
                 cert_file = CONF.ssl_cert_file
                 key_file = CONF.ssl_key_file
 
+                if ca_file and not os.path.exists(ca_file):
+                    raise RuntimeError(
+                          _("Unable to find ca_file : %s") % ca_file)
                 if cert_file and not os.path.exists(cert_file):
                     raise RuntimeError(_("Unable to find cert_file : %s") %
                                        cert_file)
-
                 if key_file and not os.path.exists(key_file):
                     raise RuntimeError(_("Unable to find key_file : %s") %
                                        key_file)
-
                 if self._use_ssl and (not cert_file or not key_file):
                     raise RuntimeError(_("When running server in SSL mode, "
                                          "you must specify both a cert_file "
@@ -180,6 +185,10 @@ class Server(ServiceBase):
                     'cert_reqs': ssl.CERT_NONE,
                 }
 
+                if ca_file:
+                    ssl_kwargs['ca_certs'] = ca_file
+                    ssl_kwargs['cert_reqs'] = ssl.CERT_REQUIRED
+
                 dup_socket = eventlet.wrap_ssl(dup_socket,
                                                **ssl_kwargs)
             except Exception: