>> ^jwray:
Technically Central America does not include any part of Mexico

My understanding is that it is customary to use either the Isthmus of Tehuantepec or the Trans-Mexican Volcanic Belt is the northerly inland border of north/central America, which, either way, makes a good chunk of Mexico part of central. While Mexico is not considered a "Central American country" since most of it is in North America, everyone I know who lives or grow up in Mexico is of the very clear impression that their country is in both north and central. While I was living in Mexico I flipped through some of the standard elementary curricula, and was surprised that they used the Volcanic Belt as the geographic border, which actually puts DF pretty close to the line.