Word censor and disallow username

[imlek]

Hi,

Is Vbulletin have feature of:

Disallow username?

I would like some username with certain prefix or suffix not allowed to be registered, because it will be used for official username.
In Admin demo, I found:

Illegal User Names
Enter names in here that you do not want people to be able to register.
If any of the names here are included within the username, the user will told that there is an error. For example, if you make the name John illegal, the name Johnathan will also be disallowed.

But this is not the one I need.
I need if I put John, every user-name begin with "John" will not allowed, but if the is "john" in the middle of user-name, it is allowed, example: maryjohn


Please advice.

Thank you.

[Steve Machol]

There is currently no option to do this in the default vB.