Hi,
This is a problem for us. However, the sheer number of spam account registrations makes this a difficult one to resolve. If people e-mail me, I'll do my best to manually register such failed registrations.
If it's helpful, I could include all the moderators on the e-mail inbox for such questions. The downside is that this account receives a lot of spam - so all the moderators would also get this spam.
It's a difficult balance between annoying potential new members and annoying the site with spam forum posts.
Ben