+#if defined(SOL2)
+#include <netinet/in.h>
+
+typedef union {
+ uint8_t e8[8]; /* lower 64-bit IPv6 address */
+ uint32_t e32[2]; /* lower 64-bit IPv6 address */
+} eui64_t;
+
+/*
+ * Declare the two below, since in.h only defines them when _KERNEL
+ * is declared - which shouldn't be true when dealing with user-land programs
+ */
+#define s6_addr8 _S6_un._S6_u8
+#define s6_addr32 _S6_un._S6_u32
+
+#else /* else if not defined(SOL2) */
+
+/*
+ * TODO:
+ *
+ * Maybe this should be done by processing struct in6_addr directly...
+ */
+typedef union
+{
+ u_int8_t e8[8];
+ u_int16_t e16[4];
+ u_int32_t e32[2];
+} eui64_t;
+
+#endif /* defined(SOL2) */