Really? I always assumed it to be a fairly universal thing, besides the A6M3 Model 32 being called the Hamp.
When the Allies first encountered the A6M3 Model 32, they thought it was a new model and gave it the name "Hamp". When it was soon realized that the Model 32 was just a variant of the Zero, "Hamp" was dropped and given the Allied code name of "Zeke 32".
Kind of a funny story behind the first Allied name designation. When Allies first encountered the Model 32, they thought it was a new model because the changes to the appearance. Supposedly, the original code name was "Hap" in honor of General "Hap" Arnold but he strongly objected to having his name associated with a Japanese plane and a "M" was added to make the name "Hamp". That's why sometimes you'll see the Model 32 referred to as "Hap / Hamp".
Or it could be that all Zeros are Zekes and all Zekes are Zeros. Allied code name designations for fighters were all male names, so Zeke (being a male name) was used to name the Zero since it was the A6M Type 0.
ack-ack
