I keep getting the error that my crontab file is corrupt:

# Any output generated by the cron entries below is sent to the e-mail
# address assigned to the MAILTO environment variable.

# Execute the "vnukelog" command at 11:40 PM (40 23) on the first day (1)
# of each month.
40 23 1 * *  /usr/local/bin/vnukelog

#end of file
It is telling me that there is a bad day-of-month, but it correct! whats the deal?

I am running this command:

% crontab ~/cronjobs.crj
(that file is called cronjobs.crj above)