Search Mail Logs Causing Runaway Perl Process

If a user selects "Logs & Reports" >> "Search Mail Logs" and hits the button, nothing seems to happen.

However the server CPU load starts ramping up, and if the user starts more such processes the box starts to die!

The process is "/usr/libexec/webmin/virtual-server/maillog.cgi".

Is this a bug? Or something wrong with my system? (VM Pro on CentOS 5 with 2Gb RAM)

Is there a way I can fix this to protect the server? i.e "if maillog.cgi has taken longer than 20 seconds, kill it!" (or some such)