diff --git a/configure.ac b/configure.ac
index 3bb6184..f1c33bd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -16,18 +16,25 @@ AM_PROG_CC_C_O
 AM_PROG_AS
 AC_PROG_RANLIB
 
-dnl Checks for header files.
+dnl Checks for header files
 AC_HEADER_STDC
-AC_CHECK_HEADERS([sys/param.h syslog.h])
+AC_CHECK_HEADERS([sys/endian.h sys/param.h syslog.h])
 # sys/sysctl.h requires sys/types.h on FreeBSD
 # sys/sysctl.h requires sys/param.h on OpenBSD
 AC_CHECK_HEADERS([sys/sysctl.h], [], [],
 [#include <sys/types.h>
-#if HAVE_SYS_PARAM_H
+#ifdef HAVE_SYS_PARAM_H
 #include <sys/param.h>
 #endif
 ])
 
+AC_CHECK_DECLS([be32dec, le32dec, be32enc, le32enc], [], [],
+[AC_INCLUDES_DEFAULT
+#ifdef HAVE_SYS_ENDIAN_H
+#include <sys/endian.h>
+#endif
+])
+
 AC_FUNC_ALLOCA
 
 case $target in
diff --git a/miner.h b/miner.h
index 31f464d..348da54 100644
--- a/miner.h
+++ b/miner.h
@@ -77,13 +77,29 @@ static inline uint32_t swab32(uint32_t v)
 #endif
 }
 
+#ifdef HAVE_SYS_ENDIAN_H
+#include <sys/endian.h>
+#endif
+
+#if !HAVE_DECL_BE32DEC
 static inline uint32_t be32dec(const void *pp)
 {
 	const uint8_t *p = (uint8_t const *)pp;
 	return ((uint32_t)(p[3]) + ((uint32_t)(p[2]) << 8) +
 	    ((uint32_t)(p[1]) << 16) + ((uint32_t)(p[0]) << 24));
 }
+#endif
 
+#if !HAVE_DECL_LE32DEC
+static inline uint32_t le32dec(const void *pp)
+{
+	const uint8_t *p = (uint8_t const *)pp;
+	return ((uint32_t)(p[0]) + ((uint32_t)(p[1]) << 8) +
+	    ((uint32_t)(p[2]) << 16) + ((uint32_t)(p[3]) << 24));
+}
+#endif
+
+#if !HAVE_DECL_BE32ENC
 static inline void be32enc(void *pp, uint32_t x)
 {
 	uint8_t *p = (uint8_t *)pp;
@@ -92,14 +108,9 @@ static inline void be32enc(void *pp, uint32_t x)
 	p[1] = (x >> 16) & 0xff;
 	p[0] = (x >> 24) & 0xff;
 }
+#endif
 
-static inline uint32_t le32dec(const void *pp)
-{
-	const uint8_t *p = (uint8_t const *)pp;
-	return ((uint32_t)(p[0]) + ((uint32_t)(p[1]) << 8) +
-	    ((uint32_t)(p[2]) << 16) + ((uint32_t)(p[3]) << 24));
-}
-
+#if !HAVE_DECL_LE32ENC
 static inline void le32enc(void *pp, uint32_t x)
 {
 	uint8_t *p = (uint8_t *)pp;
@@ -108,6 +119,7 @@ static inline void le32enc(void *pp, uint32_t x)
 	p[2] = (x >> 16) & 0xff;
 	p[3] = (x >> 24) & 0xff;
 }
+#endif
 
 void sha256_init(uint32_t *state);
 void sha256_transform(uint32_t *state, const uint32_t *block, int swap);