diff --git a/header_test.go b/header_test.go
index 0312a99..424f1ed 100644
--- a/header_test.go
+++ b/header_test.go
@@ -13,19 +13,22 @@ import (
 // Stuff to be used in both versions tests.
 
 const (
-	NO_PROTOCOL  = "There is no spoon"
-	IP4_ADDR     = "127.0.0.1"
-	IP6_ADDR     = "::1"
-	PORT         = 65533
-	INVALID_PORT = 99999
+	NO_PROTOCOL     = "There is no spoon"
+	IP4_ADDR        = "127.0.0.1"
+	IP6_ADDR        = "::1"
+	IP6_COMPAT_ADDR = "0:0:0:0:0:ffff:7f00:1"
+	PORT            = 65533
+	INVALID_PORT    = 99999
 )
 
 var (
-	v4ip = net.ParseIP(IP4_ADDR).To4()
-	v6ip = net.ParseIP(IP6_ADDR).To16()
+	v4ip       = net.ParseIP(IP4_ADDR).To4()
+	v6ip       = net.ParseIP(IP6_ADDR).To16()
+	v6CompatIP = net.ParseIP(IP4_ADDR).To16()
 
-	v4addr net.Addr = &net.TCPAddr{IP: v4ip, Port: PORT}
-	v6addr net.Addr = &net.TCPAddr{IP: v6ip, Port: PORT}
+	v4addr       net.Addr = &net.TCPAddr{IP: v4ip, Port: PORT}
+	v6addr       net.Addr = &net.TCPAddr{IP: v6ip, Port: PORT}
+	v6CompatAddr net.Addr = &net.TCPAddr{IP: v6CompatIP, Port: PORT}
 
 	v4UDPAddr net.Addr = &net.UDPAddr{IP: v4ip, Port: PORT}
 	v6UDPAddr net.Addr = &net.UDPAddr{IP: v6ip, Port: PORT}
diff --git a/v1.go b/v1.go
index 49d23c6..08efe9a 100644
--- a/v1.go
+++ b/v1.go
@@ -114,11 +114,16 @@ func parseV1PortNumber(portStr string) (int, error) {
 	return port, nil
 }
 
-func parseV1IPAddress(protocol AddressFamilyAndProtocol, addrStr string) (addr net.IP, err error) {
-	addr = net.ParseIP(addrStr)
-	tryV4 := addr.To4()
-	if (protocol == TCPv4 && tryV4 == nil) || (protocol == TCPv6 && tryV4 != nil) {
-		err = ErrInvalidAddress
+func parseV1IPAddress(protocol AddressFamilyAndProtocol, addrStr string) (net.IP, error) {
+	ip := net.ParseIP(addrStr)
+	switch protocol {
+	case TCPv4:
+		ip = ip.To4()
+	case TCPv6:
+		ip = ip.To16()
 	}
-	return
+	if ip == nil {
+		return nil, ErrInvalidAddress
+	}
+	return ip, nil
 }
diff --git a/v1_test.go b/v1_test.go
index 9b72a79..9b8083b 100644
--- a/v1_test.go
+++ b/v1_test.go
@@ -12,9 +12,11 @@ var (
 	TCP4AddressesAndPorts        = strings.Join([]string{IP4_ADDR, IP4_ADDR, strconv.Itoa(PORT), strconv.Itoa(PORT)}, separator)
 	TCP4AddressesAndInvalidPorts = strings.Join([]string{IP4_ADDR, IP4_ADDR, strconv.Itoa(INVALID_PORT), strconv.Itoa(INVALID_PORT)}, separator)
 	TCP6AddressesAndPorts        = strings.Join([]string{IP6_ADDR, IP6_ADDR, strconv.Itoa(PORT), strconv.Itoa(PORT)}, separator)
+	TCP6CompatAddressesAndPorts  = strings.Join([]string{IP6_COMPAT_ADDR, IP6_ADDR, strconv.Itoa(PORT), strconv.Itoa(PORT)}, separator)
 
-	fixtureTCP4V1 = "PROXY TCP4 " + TCP4AddressesAndPorts + crlf + "GET /"
-	fixtureTCP6V1 = "PROXY TCP6 " + TCP6AddressesAndPorts + crlf + "GET /"
+	fixtureTCP4V1       = "PROXY TCP4 " + TCP4AddressesAndPorts + crlf + "GET /"
+	fixtureTCP6V1       = "PROXY TCP6 " + TCP6AddressesAndPorts + crlf + "GET /"
+	fixtureTCP6CompatV1 = "PROXY TCP6 " + TCP6CompatAddressesAndPorts + crlf + "GET /"
 )
 
 var invalidParseV1Tests = []struct {
@@ -54,7 +56,7 @@ var invalidParseV1Tests = []struct {
 func TestReadV1Invalid(t *testing.T) {
 	for _, tt := range invalidParseV1Tests {
 		if _, err := Read(tt.reader); err != tt.expectedError {
-			t.Fatalf("TestReadV1Invalid: expected %s, actual %s", tt.expectedError, err.Error())
+			t.Fatalf("TestReadV1Invalid: expected %s, actual %s", tt.expectedError, err)
 		}
 	}
 }
@@ -83,6 +85,16 @@ var validParseAndWriteV1Tests = []struct {
 			DestinationAddr:   v6addr,
 		},
 	},
+	{
+		bufio.NewReader(strings.NewReader(fixtureTCP6CompatV1)),
+		&Header{
+			Version:           1,
+			Command:           PROXY,
+			TransportProtocol: TCPv6,
+			SourceAddr:        v6CompatAddr,
+			DestinationAddr:   v6addr,
+		},
+	},
 }
 
 func TestParseV1Valid(t *testing.T) {