Postgrey restart issue with wrong Regexp

Activate Greylisting and add to your whitelisted clients a hostname like this *.virtualmin.com. Virtualmin allows saving nothing wrong happening. Now click on that hostname for editing and check the box for Regular expression match option. This is a scenario for a newbie who doesn't know what is doing. Click on [Save] button.

After saving you will see [Enable Greylisting] button. Click on it. You will see an error message like this:

Starting Postgrey server .. .. startup failed : Starting postfix greylisting daemon: postgreyQuantifier follows nothing in regex; marked by <-- HERE in m/* <-- HERE .virtualmin.com/ at /usr/sbin/postgrey line 64, line 10. failed!

There are no other options from now on to correct that mistake unchecking the box for Regular expression match option. You are in a loop of pages and Postgrey will not start! The only way to fix this is using the Terminal and editing manually /etc/postgrey/whitelist_clients file. If it is a newbie it won't have a solution pretty quick for sure. This needs a fix, a button for editing the mistake.