diff --git a/examples/sample.source.PKIX1/config.h b/examples/sample.source.PKIX1/config.h
index e9a97e66..63b2105e 100644
--- a/examples/sample.source.PKIX1/config.h
+++ b/examples/sample.source.PKIX1/config.h
@@ -4,5 +4,6 @@ extern int opt_debug;
 #define	ASN_DEBUG(fmt, args...)	do {		\
 		if(opt_debug < 2) break;	\
 		fprintf(stderr, fmt, ##args);	\
-		fprintf(stderr, "\n");		\
+		fprintf(stderr, " (%s:%d)\n",	\
+			__FILE__, __LINE__);	\
 	} while(0)