e-Mail aliases blocked?

I just noticed something quite strange … but first the background: For my primary email address I use an alias set through my domain provider that redirects the emails to my gmail account. When I send email I specify my domain-mail-address as sender simply because if I change the mail provider (again) I won’t have to change all the profiles on all these forums I’m registered ;-)

In a previous post I mentioned that I couldn’t subscribe to the del.icio.us mailing list. No I wanted to post to the WSG mailinglist, but this was also in vain. So I started to play a little bit around and noticed, that if I send the mail through gmail itself, there is no problem subscribing to the del.icio.us list :-? So there must be somewhere a domain check comparing the actually sender domain with the domain part of the sender e-mail address.

While I completely understand that this check is necessary to prevent spoofing/phishing it’s still at least for me very annoying since I can’t really afford a real mailserver to send my mails… although, actually sending shouldn’t be a big problem since I normally don’t send too many large mails per month. Still, it’s really annoying for me since it used to work quite fine before :-(