1. A method of recognizing an identifier entered by a user, the identifier including a first plurality of predetermined characters, wherein the characters are selected from a first set of characters, the first set of characters having a first total number of characters, the method comprising the steps of: a) providing a recognized identifier based on the entered identifier, the recognized identifier comprising a second plurality of predetermined characters; b) providing a plurality of reference identifiers, each one of the plurality of reference identifiers comprising a different plurality of predetermined characters, each one of the different plurality of predetermined characters belonging to the first set of characters; c) providing a first arrangement of character recognition probabilities, the first arrangement of character recognition probabilities encompassing a second set of characters having a second total number of characters and is a superset of the characters of the first set of characters; d) producing a constrained arrangement of character recognition probabilities by constraining the first arrangement of character recognition probabilities to encompass a third set of characters constituting a subset of the second set of characters; e) obtaining, for each character position in at least one of the reference identifiers and each character position in the recognized identifier, from the constrained arrangement of character recognition probabilities, a probability that a character in the at least one reference identifier is recognized as a character found in the corresponding character position in the recognized identifier; f) determining an identifier recognition probability based on the obtained probabilities; g) repeating steps e) and f) for every reference identifier in the plurality of reference identifiers, each one of the plurality of reference identifiers being associated with a corresponding identifier recognition probability; and h) selecting the reference identifier most likely matching the entered identifier based on the plurality of obtained recognition probabilities.