Pina Colada

[Bapopik at AOL.COM]

   THE SERVER (also, THE BAR SERVER) is a bartending magazine.  The LOC has
it from 1962-1971.  I briefly looked through it for "pina colada."
   A Mexican menu from "Su Casa" (no fajitas or chimichangas, unfortunately)
is given in THE SERVER, November-December 1966, pg. 37, col. 2:

   _MEXICAN DRINKS_
   MARGARITA 1.00
TEQUILA, CONTREAU, FRESH LIME JUICE
   PINA COLADA 1.00 ??RUM??
   TEQUILA SOUR 1.00
TEQUILA, FRESH LIME JUICE
   CAFE CHIAPAS 1.00
A SU CASA SPECIALTY
   MEXITINI 1.00 (Muy Seco)
TEQUILA, DRY VERMOUTH, WHOLE MEXICAN PEPPER
   TEQUILA COCKTAIL 1.00
   SANGRITA DE LA VIUDA 1.00
A MEXICAN BLOODY MARY
   TEQUILA, STRAIGHT .85
FRESH LIME WEDGE AND SALT
   DANIEL DE ORO 1.00
A MEXICAN SCREWDRIVER
   BANDERA 1.25
A FLAMING TOAST TO MEXICO
   PECHUGA ALMENDRADA 1.00
ALMOND FLAVORED BRANDY IMPORTED FROM MEXICO
   WET BACK 1.00
KAHLUA AND TEQUILA ON THE ROCKS
   BERTA 1.00

   Why is "pina colada" on this list, with those question marks?