6. The method of claim 1 , wherein the target entry is a character string comprising letters of a pre-selected alphabet, wherein the plurality of potential distractors comprises the pre-selected alphabet, and wherein the step of selecting at least one distractor comprises iteratively selecting for each character of the character string every letter of the pre-selected alphabet that is acoustically dissimilar to a particular character of the character string.
6. The method of claim 1 , wherein the target entry is a character string comprising letters of a pre-selected alphabet, wherein the plurality of potential distractors comprises the pre-selected alphabet, and wherein the step of selecting at least one distractor comprises iteratively selecting for each character of the character string every letter of the pre-selected alphabet that is acoustically dissimilar to a particular character of the character string. 7. The method of claim 6 , wherein the step of generating a speech recognition grammar comprises generating for each character of the character string a corresponding pool of distractors that comprises each letter of the pre-selected alphabet that is acoustically dissimilar to the corresponding character.