I got a Mailblocks account back during the introduction when they were $10 for 3 years. At that time their IMAP server couldn’t handle requests from my favorite text-mode mail user-agent (MUA) Pine. I sent their technical support folks several messagea about it but never got anything even remotely satisfying from them. Well, the challenge/response model has lost some of its sparkle and I just kinda let it lie. They relaunched a week or two ago with a new version of their system and apparently they fixed their IMAP server, too, cause now it works just fine with Pine.