diff --git a/ext/lwipopts.h b/ext/lwipopts.h
index 91dafe0..03409f3 100644
--- a/ext/lwipopts.h
+++ b/ext/lwipopts.h
@@ -46,10 +46,10 @@
 
 // IPV6 Related
 //#if defined(SDK_IPV6)
-	#define LWIP_IPV6   0
+	#define LWIP_IPV6   1
 //#endif
 //#if defined(SDK_IPV4) 
-	#define LWIP_IPV4   1
+	#define LWIP_IPV4   0
 //#endif
 
 #define LWIP_TCP 1
diff --git a/src/utils.hpp b/src/sdkutils.hpp
similarity index 100%
rename from src/utils.hpp
rename to src/sdkutils.hpp
diff --git a/src/tap.cpp b/src/tap.cpp
index 104c9a1..3543fe9 100644
--- a/src/tap.cpp
+++ b/src/tap.cpp
@@ -36,7 +36,7 @@
 #include <sys/syscall.h>
 
 #include "tap.hpp"
-#include "utils.hpp"
+#include "sdkutils.hpp"
 #include "sdk.h"
 #include "defs.h"
 #include "debug.h"
diff --git a/src/tap.hpp b/src/tap.hpp
index 0b9ef02..99d8295 100644
--- a/src/tap.hpp
+++ b/src/tap.hpp
@@ -497,10 +497,10 @@ namespace ZeroTier {
 	 	 */
 		void closeConnection(PhySocket *sock);
 
+	#if defined(SDK_PICOTCP)
 		ip_addr_t convert_ip(struct sockaddr_in * addr)
 		{
 		  ip_addr_t conn_addr;
-		 
 		  struct sockaddr_in *ipv4 = addr;
 		  short a = ip4_addr1b(&(ipv4->sin_addr));
 		  short b = ip4_addr2b(&(ipv4->sin_addr));
@@ -510,6 +510,7 @@ namespace ZeroTier {
 		 
 		  return conn_addr;
 		}
+	#endif
 
 		Phy<NetconEthernetTap *> _phy;
 		PhySocket *_unixListenSocket;