Document NASM version requirement for 64-bit backward compatible build
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@219 632fc199-4ca6-4c93-a231-07263d6284db
diff --git a/BUILDING.txt b/BUILDING.txt
index f66d7b0..349911c 100644
--- a/BUILDING.txt
+++ b/BUILDING.txt
@@ -150,7 +150,8 @@
LDFLAGS='-isysroot /Developer/SDKs/MacOSX10.4u.sdk \
-mmacosx-version-min=10.4'
-to the configure command line. The OS X 10.4 SDK must be installed.
+to the configure command line. The OS X 10.4 SDK, and NASM 2.07 or later from
+MacPorts, must be installed.
32-bit Backward-Compatible Library Build on OS/X