In Mac OS X Lion, Apple deprecated the use of the system OpenSSL library
in favour of their CommonCrypto library.  This change adds a work-around
that allows nginx to still be built on Lion with OpenSSL.

src/os/unix/ngx_darwin_config.h

diff --git a/src/os/unix/ngx_darwin_config.h b/src/os/unix/ngx_darwin_config.h
index 88aa6f5..a3a14c4 100644
--- a/src/os/unix/ngx_darwin_config.h
+++ b/src/os/unix/ngx_darwin_config.h
@@ -8,6 +8,8 @@
 #define _NGX_DARWIN_CONFIG_H_INCLUDED_
 
 
+#define MAC_OS_X_VERSION_MIN_REQUIRED MAC_OS_X_VERSION_10_0
+
 
 #include <sys/types.h>
 #include <sys/time.h>