diff --git a/uri.c b/uri.c
index 2bd5720..6e09018 100644
--- a/uri.c
+++ b/uri.c
@@ -2024,7 +2024,7 @@ xmlBuildURI(const xmlChar *URI, const xmlChar *base) {
     }
     if (bas->authority != NULL)
        res->authority = xmlMemStrdup(bas->authority);
-    else if (bas->server != NULL) {
+    else if ((bas->server != NULL) || (bas->port == -1)) {
        res->server = xmlMemStrdup(bas->server);
        if (bas->user != NULL)
            res->user = xmlMemStrdup(bas->user);