logwatch -save option

[redhat at buglecreek.com]

I'm trying to setup logwatch to save it's output to /tmp/logwatch.`date
+%F`.  I have modified the save option in logwatch.conf with
/tmp/logwatch.`date +%F`, but it does not seem to recognize bash
command substitution.  Maybe because it is written in perl?  Does anyone
know of a way to accomplish this?  Am I missing something obvious?   
Since sendmail is turned off on our systems, this would at least let us
view the logwatch output until a better solution can be made. 

Thanks