Remove all signatures to search engines from certain urls?

[fcreature]

I've been receiving a ton of spam from members of Marapets.com posting in their signature using their Marapets.com signature and I was wondering if a hack could be made to do the following:

-Block urls from certain sites from being displayed in their signature to search engines
-Add nofollow if this isn't possible.

[StGaensler]

It is possible to hide signatures from search engines generally. Do you mean that?
Add the bold code to your postbit(_legacy) template:<if condition="$post['signature']&&!$show['search_engine']">

[fcreature]

No, I mean to block out urls from showing that is from a certain site...
Like, links going out from Marapets.com or something.

[peterska2]

Two solutions I can think of off the top of my head that don't require any modifications.

Add marapets to the censor list found under vBOptions;
Set up a replacement variable (Styles and Templates > Replacement variable manager) for marapets.com to display something else like I am an idiotic spammer or whatever you want