diff --git a/cmd/mtwebmapper/tilesupdater.go b/cmd/mtwebmapper/tilesupdater.go
index 04ff529..0a4e6c8 100644
--- a/cmd/mtwebmapper/tilesupdater.go
+++ b/cmd/mtwebmapper/tilesupdater.go
@@ -96,15 +96,16 @@ func (tu *tileUpdater) checkIP(r *http.Request) bool {
 		return true
 	}
 
-	var host []string
-	if host = strings.SplitN(r.RemoteAddr, ":", 2); len(host) < 1 {
+	idx := strings.LastIndex(r.RemoteAddr, ":")
+	if idx < 0 {
 		log.Printf("WARN: cannot extract host from '%s'.\n", r.RemoteAddr)
 		return false
 	}
 
-	var ip net.IP
-	if ip = net.ParseIP(host[0]); ip == nil {
-		log.Printf("WARN: cannot get IP for host '%s'.\n", host[0])
+	host := strings.Trim(r.RemoteAddr[:idx], "[]")
+	ip := net.ParseIP(host)
+	if ip == nil {
+		log.Printf("WARN: cannot get IP for host '%s'.\n", host)
 		return false
 	}