go.crypto/ssh: add workaround for broken port forwarding in
OpenSSH 5.

Tested with OpenSSH_5.9

R=agl, dave
CC=golang-dev
https://golang.org/cl/11921043
diff --git a/ssh/tcpip_test.go b/ssh/tcpip_test.go
new file mode 100644
index 0000000..7fa9fc4
--- /dev/null
+++ b/ssh/tcpip_test.go
@@ -0,0 +1,16 @@
+package ssh
+
+import (
+	"testing"
+)
+
+func TestAutoPortListenBroken(t *testing.T) {
+	broken := "SSH-2.0-OpenSSH_5.9hh11"
+	works := "SSH-2.0-OpenSSH_6.1"
+	if !isBrokenOpenSSHVersion(broken) {
+		t.Errorf("version %q not marked as broken", broken)
+	}
+	if isBrokenOpenSSHVersion(works) {
+		t.Errorf("version %q marked as broken", works)
+	}
+}