diff --git a/cryptfs.h b/cryptfs.h
index 432450c..ca3cc95 100644
--- a/cryptfs.h
+++ b/cryptfs.h
@@ -62,7 +62,7 @@
   int cryptfs_check_passwd(char *pw);
   int cryptfs_restart(void);
   int cryptfs_enable(char *flag, char *passwd);
-  int cryptfs_changepw(char *oldpw, char *newpw);
+  int cryptfs_changepw(char *newpw);
 #ifdef __cplusplus
 }
 #endif