17. The system as claimed in claim 12 , further comprising: a message header converting component for receiving a message having a message header of header names, and further comprising: a look-up component for converting the header names to canonical keys; and a list building component for building a message header list for the message of the canonical keys with integer values.
12. A system, comprising: a converter for converting header names into a canonical form comprising a plurality of canonical keys, wherein each canonical key represents at least one equivalent header name, and wherein each canonical key has a string and an integer value; a map for mapping between the header names and the canonical keys; and a header search component for searching for a header name using the canonical key by sequential search using integer comparison.