Me too, I was worried that it was due to the January 20-21st hacking incident on TIMGUL and the smaller hacking attempts that occured until I switched from IPB 1.3.1 (not the modded invisionfree one, the official one that is filled with exploits) to SMF and changed passwords. The hacker installed a script that sent about 50000 spam emails in a few hours to over 9000 people, then there were multiple complaints and 1and1 suspended my account for spam. But afterward after this was fixed spambots started using e-mail spoofing more and more and I started getting a lot of e-mails from them, but the e-mail address listed is o m n i m a g a @ g m a i l . c o m, even thought the e-mail didn,t came from there. There's nothing wrong on my webspace now, but I was worried that this caused my e-mail address to be blacklisted as spam address by many e-mail service providers, causing most people to not receive the e-mails. I think something similar happened to calc.org e-mail service provider back in the days. BUt finally it just turned out to be a misconfiguration in the settings that I didn't noticed before.
Btw TIMGUL is hosted on the same webspace than Omnimaga.