SophosBusy.lock ownership problem

[Stephen Lee]

Hi,
I'm running mailscanner-4.20-3/Exim3.36/Sophos3.68 on RH7.3. Once in a
while, the /tmp/SophosBusy.lock file gets created with root.root
ownership. This causes problems as I run MS as exim.exim so an old
/tmp/SophosBusy.lock with root.root ownership can't be removed. Here's a
bit of the log:

May 10 04:59:28 qcfl MailScanner[17357]: Virus and Content Scanning:
Starting
May 10 04:59:28 qcfl MailScanner[17357]: Cannot create
/tmp/SophosBusy.lock, Permission denied

Am I missing a config setting somewhere? MS was installed from RPM.

Thanks,
Stephen