Does anybody know why, at the end of section 7.6 of the ECMA-262, 5th Edition specification, the nonterminals UnicodeLetter, UnicodeCombiningMark, UnicodeDigit, UnicodeconnectorPunctuation, and UnicodeEscapeSequence are not followed by two colons?

From section 5.1.6:

Nonterminal symbols are shown in italic type. The definition of a nonterminal is introduced by the name of the nonterminal being defined followed by one or more colons. (The number of colons indicates to which grammar the production belongs.)

Since lexical productions are distinguished by having two colons, and this is under "Lexical Conventions", I'm assuming that they meant to put the colons in. Does that sound right?

Just making sure that these really are nonterminals and they really are part of the lexical grammar.

EDIT:

I noticed there have been votes to close this. Just to make my case about why this is programming-related, it is relevant to anyone wanting to implement an ECMAScript interpreter.