diff -up thunderbird-10.0/comm-release/mozilla/ipc/chromium/src/base/data_pack.cc.secondary-ipc thunderbird-10.0/comm-release/mozilla/ipc/chromium/src/base/data_pack.cc
--- thunderbird-10.0/comm-release/mozilla/ipc/chromium/src/base/data_pack.cc.secondary-ipc	2012-01-29 15:44:23.000000000 +0100
+++ thunderbird-10.0/comm-release/mozilla/ipc/chromium/src/base/data_pack.cc	2012-01-31 10:45:57.784248018 +0100
@@ -91,14 +91,7 @@ bool DataPack::Load(const FilePath& path
 bool DataPack::Get(uint32_t resource_id, StringPiece* data) {
   // It won't be hard to make this endian-agnostic, but it's not worth
   // bothering to do right now.
-#if defined(__BYTE_ORDER)
-  // Linux check
-  COMPILE_ASSERT(__BYTE_ORDER == __LITTLE_ENDIAN,
-                 datapack_assumes_little_endian);
-#elif defined(__BIG_ENDIAN__)
-  // Mac check
-  #error DataPack assumes little endian
-#endif
+#warning DoTheRightThingMakingThisEndianAgnostic!
 
   DataPackEntry* target = reinterpret_cast<DataPackEntry*>(
       bsearch(&resource_id, mmap_->data() + kHeaderLength, resource_count_,
diff -up thunderbird-10.0/comm-release/mozilla/ipc/chromium/src/build/build_config.h.secondary-ipc thunderbird-10.0/comm-release/mozilla/ipc/chromium/src/build/build_config.h
--- thunderbird-10.0/comm-release/mozilla/ipc/chromium/src/build/build_config.h.secondary-ipc	2012-01-29 15:44:23.000000000 +0100
+++ thunderbird-10.0/comm-release/mozilla/ipc/chromium/src/build/build_config.h	2012-01-31 10:53:24.409935119 +0100
@@ -65,10 +65,10 @@
 #elif defined(__ppc__) || defined(__powerpc__)
 #define ARCH_CPU_PPC 1
 #define ARCH_CPU_32_BITS 1
-#elif defined(__sparc64__)
+#elif defined(__sparc__) && !defined(__arch64)
 #define ARCH_CPU_SPARC 1
 #define ARCH_CPU_64_BITS 1
-#elif defined(__sparc__)
+#elif defined(__sparc__) && defined(__arch64)
 #define ARCH_CPU_SPARC 1
 #define ARCH_CPU_32_BITS 1
 #elif defined(__mips__)
diff -up thunderbird-10.0/comm-release/mozilla/ipc/chromium/src/chrome/common/ipc_message_utils.h.secondary-ipc thunderbird-10.0/comm-release/mozilla/ipc/chromium/src/chrome/common/ipc_message_utils.h