diff --git a/library/ssl_cache.c b/library/ssl_cache.c
index 4c7d3db..69f7114 100644
--- a/library/ssl_cache.c
+++ b/library/ssl_cache.c
@@ -27,7 +27,11 @@
  * to store and retrieve the session information.
  */
 
+#if !defined(POLARSSL_CONFIG_FILE)
 #include "polarssl/config.h"
+#else
+#include POLARSSL_CONFIG_FILE
+#endif
 
 #if defined(POLARSSL_SSL_CACHE_C)