Can't get this crontab entry to work

[David <david@davesbackpages.com>]

 12 8 * * * tar -cf /lin2/backup_deb_`date +%m%d%y` /home /etc /var/www


 I keep getting the following error message in my mailbox from cron:

 /bin/sh: -c: line 1: unexpected EOF while looking for matching ``'
 /bin/sh: -c: line 2: syntax error: unexpected end of file

What am I doing wrong?

I was able to run the cron job without the time stamp, but now I really
would like to add it and I don't seem to be having much luck.  I think
its the backtics that are giving me the problem.