Yea they blocked my IP but I'm still able to send emails from different servers not located at ThePlanet but not Them, yep I think that solved my case

*sarcasm*

If I'm able to send emails USING my ISP... and Other servers that are on the net, but just not server matrix (tried it on a friends server as well who has it with SM), definately a problem with SM and not me or the server. :P