cmd/btrtrc/main.go | 12 ++++++++++--

diff --git a/cmd/btrtrc/main.go b/cmd/btrtrc/main.go
index 35880d9eeff85107c868f6955dd23515e1c26691..eb5afaab76ab400a922db8be3ed3e6943321990e 100644
--- a/cmd/btrtrc/main.go
+++ b/cmd/btrtrc/main.go
@@ -57,8 +57,16 @@ 		doVerify(cc, flag.Args())
 		return
 	}
 	cc.Seed = true
-	cc.PublicIp4 = net.ParseIP(*pub4).To4()
-	cc.PublicIp6 = net.ParseIP(*pub6).To16()
+	if *pub4 == "" {
+		cc.DisableIPv4 = true
+	} else {
+		cc.PublicIp4 = net.ParseIP(*pub4).To4()
+	}
+	if *pub6 == "" {
+		cc.DisableIPv6 = true
+	} else {
+		cc.PublicIp6 = net.ParseIP(*pub6).To16()
+	}
 	cc.NoDHT = *noDHT
 	cc.SetListenAddr(*addr)
 	client, err := torrent.NewClient(cc)