diff --git a/option.h b/option.h
index 57088a01..95772119 100644
--- a/option.h
+++ b/option.h
@@ -18,59 +18,38 @@
 #include "bits.h"
 #include "pdu.h"
 
-#ifdef WORDS_BIGENDIAN
-typedef union {
-  struct {		        /* short form, to be used when length < 15 */
-    unsigned int delta:4;      /* option type (expressed as delta) */
-    unsigned int length:4;	/* number of option bytes (15 indicates extended form) */
-    /* 0--14 bytes options */
-  } sval;
-  struct {			/* extended form, to be used when lengt==15 */
-    unsigned int delta:4;      /* option type (expressed as delta) */
-    unsigned int flag:4;	/* must be 15! */
-    unsigned int length:8;	/* length - 15 */
-    /* 15--270 bytes options */
-  } lval;
-} coap_opt_t;
-#else
-typedef union {
-  struct {		        /* short form, to be used when length < 15 */
-    unsigned int length:4;	/* number of option bytes (15 indicates extended form) */
-    unsigned int delta:4;      /* option type (expressed as delta) */
-    /* 0--14 bytes options */
-  } sval;
-  struct {			/* extended form, to be used when lengt==15 */
-    unsigned int flag:4;	/* must be 15! */
-    unsigned int delta:4;      /* option type (expressed as delta) */
-    unsigned int length:8;	/* length - 15 */
-    /* 15--270 bytes options */
-  } lval;
-} coap_opt_t;
-#endif
+/** 
+ * Use byte-oriented access methods here because sliding a complex
+ * struct coap_opt_t over the data buffer may cause bus error on
+ * certain platforms.
+ */ 
+typedef unsigned char coap_opt_t;
+#define PCHAR(p) ((coap_opt_t *)(p))
 
-#define COAP_OPT_SVAL(opt) ((coap_opt_t *)(opt))->sval
-#define COAP_OPT_LVAL(opt) ((coap_opt_t *)(opt))->lval
-#define COAP_OPT_ISEXTENDED(opt) (COAP_OPT_LVAL(opt).flag == 15)
+#define COAP_OPT_ISEXTENDED(opt) ((*PCHAR(opt) & 0x0f) == 0x0f)
 
 /* these macros should be used to access fields from coap_opt_t */
-#define COAP_OPT_DELTA(opt) COAP_OPT_SVAL(opt).delta
-#define COAP_OPT_SETDELTA(opt,val) COAP_OPT_SVAL(opt).delta = (val)
+#define COAP_OPT_DELTA(opt) (*PCHAR(opt) >> 4)
+#define COAP_OPT_SETDELTA(opt,val)			\
+  (*PCHAR(opt) = (*PCHAR(opt) & 0x0f) | ((val) << 4))
 
-#define COAP_OPT_LENGTH(opt) \
-  ( COAP_OPT_ISEXTENDED(opt) ? COAP_OPT_LVAL(opt).length + 15 : COAP_OPT_SVAL(opt).length )
+#define COAP_OPT_LENGTH(opt)			\
+  ( COAP_OPT_ISEXTENDED(opt)			\
+    ? (*(PCHAR(opt) + 1) + 15)			\
+    : (*PCHAR(opt) & 0x0f))
 
-#define COAP_OPT_SETLENGTH(opt,val)		\
-  if ( (val) < 15 )				\
-    COAP_OPT_SVAL(opt).length = (val) & 0x0f;	\
+#define COAP_OPT_SETLENGTH(opt,val)					\
+  if ( ((val) & 0xff) < 15 )						\
+    *PCHAR(opt) = ((*PCHAR(opt) & 0xf0) | ((val) & 0x0f));		\
   else {								\
-    COAP_OPT_LVAL(opt).length = ((val) - 15) & 0xff;			\
-    COAP_OPT_LVAL(opt).flag = 15;					\
+    *PCHAR(opt) |= 0x0f;						\
+    *(PCHAR(opt) + 1) = ((val) & 0xff) - 15;				\
   }
 
-#define COAP_OPT_VALUE(opt)						\
-  ( (unsigned char *)(opt) + ( COAP_OPT_ISEXTENDED(opt) ? 2 : 1 ) )
+#define COAP_OPT_VALUE(opt)				\
+  (PCHAR(opt) + (COAP_OPT_ISEXTENDED(opt) ? 2 : 1))
 
-/* do not forget to adjust this when coap_opt_t is changed! */
+/* Do not forget to adjust this when coap_opt_t is changed! */
 #define COAP_OPT_SIZE(opt) ( COAP_OPT_LENGTH(opt) + ( COAP_OPT_ISEXTENDED(opt) ? 2: 1 ) )
 
 /**