syntax highlighting with javascript-mode.el and hilit19.el

[Bob Smith]

Dear all
I have the hilit19 lisp package, and also a package for text coloring 
and indentation for javascript ( javascript-mode.el).

Now in the javascript package there is a couple of lines along with:

(if (featurep 'hilit19)
  (hilit-set-mode-patterns
   'javascript-mode


...which follows many lines of keywords.

The problem is that hilit19 is not found by the script. How can I make 
it find the hilit19.elc, and what does the featurep actually do?
thank's in advance