diff --git a/src/posix.mak b/src/posix.mak
index 14f2276..b35596e 100644
--- a/src/posix.mak
+++ b/src/posix.mak
@@ -37,7 +37,7 @@ ifeq (OSX,$(TARGET))
     #SDK=/Developer/SDKs/MacOSX10.4u.sdk #doesn't work because can't find <stdarg.h>
     #SDK=/Developer/SDKs/MacOSX10.5.sdk
     #SDK=/Developer/SDKs/MacOSX10.6.sdk
-    SDK:=$(if $(filter 11.*, $(OSVER)), /Developer/SDKs/MacOSX10.5.sdk, /Developer/SDKs/MacOSX10.6.sdk)
+    SDK:=$(if $(filter 11.%, $(OSVER)), /Developer/SDKs/MacOSX10.6.sdk, /Developer/SDKs/MacOSX10.5.sdk)
     TARGET_CFLAGS=-isysroot ${SDK}
     #-syslibroot is only passed to libtool, not ld.
     #if gcc sees -isysroot it should pass -syslibroot to the linker when needed