I thought that had been fixed, by ordering the registrars not to allow problem domains (e.g. domain must be entirely in Cyrillic+Numbers or not at all), though

I thought that had been fixed, by ordering the registrars not to allow problem domains (e.g. domain must be entirely in Cyrillic+Numbers or not at all), though Wikipedia says this isn't yet the case for .com. I'm not sure if that's up-to-date though. Pretending I work for asdf.com, I could register аsdf.com (Cyrillic а) and maybe αsdf.com (Greek α) as a precaution. But "xn--sdf-5cd.com" and "xn--sdf-nxc.com" both show as unavailable for registration. Something like asclf.com (all ASCII) could be mistaken in some circumstances.