Interesting bit of Trivia

Rating: Null/10 (19 August 2004)

Possible spoiler -
Vincent's main appearance trait is his "grayness" - gray hair, gray beard, gray suit - and this point is brought home by the scene where a grey coyote crosses the street in front of their taxi.
In the original "Day of the Jackal", the Jackal's final mission begins after he makes himself "gray", by taking a drug to make his skin gray, by dyeing his hair gray, etc....
I believe the gray is meant to symbolize "the final stage" of things, whether it be the final stage of life, of a mission, etc. It can also mean great wisdom or skill - as in "gray fox" - both the Jackal and Vincent displayed a great deal of skill at what they did.