A way to change the default 027 umask of ftp is to change the entry in /etc/inetd.conf for ftpd:
ftp stream tcp6 nowait root /usr/sbin/ftpd -l -u 117
This will create files with umask 117 (mode 660).
Using the -l option will make sure the FTP sessions are logged to the syslogd. If you want to see these FTP messages in the syslogd output, then you should add in /etc/syslog.conf:
daemon.info [filename]