Isn't a "jetty" a defensive barrier to protect a harbor against storm tides? Dumb move to accidentally invite everyone to a meeting with a codename, but not a dumb codename as you protect a company from a storm.
1) Those little docks like in Venice (cf. "Let me off at this jetty" in The Last Crusade).
2) The jetty server library that Jenkins uses which shows up in error messages.
The whole point - the only purpose of a codename is that it doesn't give the game away.