-;; ... user defined identifiers \[a-zA-Z]+
- '("\\([_^-]?\\\\\\([a-zA-Z][a-zA-Z]*\\)\\)" 1 font-lock-constant-face)
+;; ... user defined identifiers, roughly \[a-zA-Z]+ with single - or _ in between.
+ '("\\([_^-]?\\\\\\([a-zA-Z[:nonascii:]]\\(?:[-_]?[a-zA-Z[:nonascii:]]\\)*\\)\\)" 1 font-lock-constant-face)