Kinbote writes of dialling 11111 to summon first responders to the scene of the shooting (“I then dialled 11111 and returned with a glass of water to the scene of the carnage,” Vladimir Nabokov, Pale Fire, note to line 1000). At the time of these events, various countries were beginning to adopt 3-digit emergency telephone numbers, following the lead of Britain’s 999. New Zealand introduced a 111 emergency number in 1958; the year before, California rolled out a ZEnith 1-2000 (presumably one asked for rather than dialled this number, since Z is not assigned a digit on the telephone dial); Australia adopted 000 in 1961. Use of 11111 for emergency purposes is undocumented, as far as my searches go.
Old World/New World: “…the disguised king’s arrival in America where he descended by parachute from a chartered plane piloted by Colonel Montacute, in a field of hay-feverish, rank-flowering weeds, near Baltimore whose oriole is not an oriole.” (note to line 691) As is often the case, a New World family of birds (the black and yellow Icteridae, “jaundiced ones”) is not closely related to its Old World namesake, in this case the orioles, family Oriolidae.
Nabokov appears to have introduced two coinages in the book, one by Shade (“And that odd muse of mine,/My versipel, is with me everywhere,/In carrel and in car, and in my chair.” [ll. 946-948]) and one by Kinbote (“The Shades were out, said the cheeky ancillula, an obnoxious little fan who came to cook for them on Sundays and no doubt dreamt of getting the old poet to cuddle her some wifeless day.” [note to line 802]). Versipel is glossed as a back-formation from versipellous, “changeable; protean; having a form, nature or appearance that changes often.” Ancillula is from the Latin, and is a diminutive of ancilla, “handmaid.”