diff --git a/include/polarssl/entropy.h b/include/polarssl/entropy.h
index 4485d3e..4f4f8f7 100644
--- a/include/polarssl/entropy.h
+++ b/include/polarssl/entropy.h
@@ -29,7 +29,11 @@
 
 #include <string.h>
 
+#if !defined(POLARSSL_CONFIG_FILE)
 #include "config.h"
+#else
+#include POLARSSL_CONFIG_FILE
+#endif
 
 #if defined(POLARSSL_SHA512_C) && !defined(POLARSSL_ENTROPY_FORCE_SHA256)
 #include "sha512.h"