Eclipse PDT - Javascript code hinting not working?

I thought Eclipse PDT had all the Javascript plugins and supported code hinting, but it's not working for me.

Was I wrong, or is there something that needs to be set up for this to 开发者_开发问答work?

Thanks in advance.

The official plugin is JSDT (Eclipse site) (many articles there, including the Using JSDT series)

The old alternative was JSEclipse (like described in this post)
Warning, this plugin might not be compatible with the official JSDT Eclipse one.

This forum post also mentions Aptana Studio as an alternative.