Sparkfun's emails blocked?

I've been trying to sign up for Sparkfun's forum, but the confirmation emails aren't getting through (either from the original signup, or from multiple "resend it" attempts). And I got no response to the "Huh?" email I sent them about it.

Has anyone else (especially anyone with Cox internet) had problems? I'm wondering whether they accidentally wound up on my ISP's Naughty List.

I would just get an hotmail or gmail adres and try that.
When that works investigate further.

Cox likes to block everyone. I'm not going to mention any company names (cause I can't remember, might be trend micro), but they use an email "SPAM" service that blacklists blocks of IP's that may only have one IP spamming.

I'm not a Cox customer but have had several issues trying to email Cox users from Amazon hosted accounts. The service they use is the only one blacklisting those IP's. The only way for companies to get un-blocked is to pay a "bribe" to the spam service blacklisting the IP.