diff -up netkit-ftp-0.17/ftp/cmds.c.acct_ovl netkit-ftp-0.17/ftp/cmds.c

--- netkit-ftp-0.17/ftp/cmds.c.acct_ovl	2011-09-09 15:36:36.087956561 +0200

+++ netkit-ftp-0.17/ftp/cmds.c	2011-09-09 15:41:16.457495370 +0200

@@ -1837,8 +1837,7 @@ account(int argc, char *argv[])

 		while (argc > 1) {

 			--argc;

 			++argv;

-			strncat(buf, *argv, sizeof(buf)-strlen(buf));

-			buf[sizeof(buf)-1] = 0;

+			strncat(buf, *argv, sizeof(buf)-strlen(buf)-1);

 		}

 		ap = buf;

 	}