--- src/mex.cc-old	2007-04-05 16:24:23.161595439 +0200
+++ src/mex.cc	2007-04-05 16:24:51.445970804 +0200
@@ -555,7 +555,7 @@
 
 	const char *p = tmp.data ();
 
-	for (int i = 0; i < buflen; i++)
+	for (int i = 0; i < nel; i++)
 	  buf[i] = p[i];
 
 	buf[nel] = 0;