diff --git a/miniupnpd/upnphttp.c b/miniupnpd/upnphttp.c
index 026731d..6f467d5 100644
--- a/miniupnpd/upnphttp.c
+++ b/miniupnpd/upnphttp.c
@@ -643,8 +643,7 @@ ProcessHTTPSubscribe_upnphttp(struct upnphttp * h, const char * path)
 	       h->req_Timeout);
 	syslog(LOG_DEBUG, "SID '%.*s'", h->req_SIDLen, h->req_buf + h->req_SIDOff);
 #if defined(UPNP_STRICT) && (UPNP_VERSION_MAJOR > 1) || (UPNP_VERSION_MINOR > 0)
-	/*if(h->req_Timeout < 1800) {*/
-	if(h->req_Timeout == 0) {
+	if(h->req_Timeout < 1800) {
 		/* Second-infinite is forbidden with UDA v1.1 and later :
 		 * (UDA 1.1 : 4.1.1 Subscription)
 		 * UPnP 1.1 control points MUST NOT subscribe using keyword infinite,
@@ -653,7 +652,13 @@ ProcessHTTPSubscribe_upnphttp(struct upnphttp * h, const char * path)
 		 * ignored by a UPnP 1.1 device (the presence of infinite is handled
 		 * by the device as if the TIMEOUT header field in a request was not
 		 * present) . The keyword infinite MUST NOT be returned by a UPnP 1.1
-		 * device. */
+		 * device.
+		 * Also the device must return a value of minimum 1800 seconds in the
+		 * response, according to UDA 1.1 (4.1.2 SUBSCRIBE with NT and CALLBACK):
+		 * TIMEOUT
+		 *   REQUIRED. Field value contains actual duration until subscription
+		 *   expires. Keyword "Second-" followed by an integer (no space).
+		 *   SHOULD be greater than or equal to 1800 seconds (30 minutes).*/
 		h->req_Timeout = 1800;	/* default to 30 minutes */
 	}
 #endif /* UPNP_STRICT */