--- channels/iax2-parser.c.orig	2010-01-28 15:00:09.000000000 -0500
+++ channels/iax2-parser.c	2011-01-07 20:59:49.000000000 -0500
@@ -42,6 +42,21 @@
 #include "iax2-parser.h"
 #include "iax2-provision.h"
 
+/* htonll and ntohll convert between network byte order (which is defined as big endian)
+ * and host byte order (which varies).   On a BIG_ENDIAN machine, these two routines do
+ * nothing.
+ * Issue #18583 shows that beginning with 1.8, when these were first used for the
+ * 64-bit expanded codec fields, Darwin PPC (BIG_ENDIAN) machines can no longer do
+ * codec negotiation with Linux i386 (LITTLE_ENDIAN) machines.
+ * It appears that the network byte order change is being handled elsewhere in the code,
+ * and that htonll and ntohll should never have been called.  However, to make that change
+ * at this point in time would introduce a new incompatibility between LITTLE_ENDIAN
+ * machines dependent on their version.
+ * This patch seeks to limit any impact by only removing the incompatibility where it must
+ * be removed: for Darwin.  For Darwin machines only, we call OSSwapInt64, since calls to
+ * xtoyll do not do the necessary swap.
+ */
+
 static int frames = 0;
 static int iframes = 0;
 static int oframes = 0;
@@ -219,7 +234,11 @@
 	char *version = (char *) value;
 	if (version[0] == 0) {
 		if (len == (int) (sizeof(format_t) + sizeof(char))) {
+#ifndef __Darwin__
 			format_t codec = ntohll(get_unaligned_uint64(value + 1));
+#else
+			format_t codec = OSSwapInt64(get_unaligned_uint64(value + 1));
+#endif
 			ast_copy_string(output, ast_getformatname(codec), maxlen);
 		} else {
 			ast_copy_string(output, "Invalid length!", maxlen);
@@ -702,7 +721,11 @@
 		unsigned char version;
 		uint64_t value;
 	} __attribute__((packed)) newval = { version, };
+#ifndef __Darwin__
 	put_unaligned_uint64(&newval.value, htonll(value));
+#else
+	put_unaligned_uint64(&newval.value, OSSwapInt64(value));
+#endif
 	return iax_ie_append_raw(ied, ie, &newval, (int) sizeof(newval));
 }
 
@@ -808,7 +831,11 @@
 						snprintf(tmp, (int)sizeof(tmp), "Expecting capability to be %d bytes long but was %d\n", (int) (sizeof(format_t) + sizeof(char)), len);
 						errorf(tmp);
 					} else {
+#ifndef __Darwin__
 						ies->capability = (format_t) ntohll(get_unaligned_uint64(data + 3));
+#else
+						ies->capability = (format_t) OSSwapInt64(get_unaligned_uint64(data + 3));
+#endif
 					}
 				} /* else unknown version */
 			}
@@ -829,7 +856,11 @@
 						snprintf(tmp, (int)sizeof(tmp), "Expecting format to be %d bytes long but was %d\n", (int) (sizeof(format_t) + sizeof(char)), len);
 						errorf(tmp);
 					} else {
+#ifndef __Darwin__
 						ies->format = (format_t) ntohll(get_unaligned_uint64(data + 3));
+#else
+						ies->format = (format_t) OSSwapInt64(get_unaligned_uint64(data + 3));
+#endif
 					}
 				} /* else unknown version */
 			}