Question: I just upgraded to Eclipse 3.4 for the second time and I think its for good now. The first time (right when it was released) was too buggy for me to stomach (mainly the PDT 2.0 plug-in); but now it seems to be all worked out.

My problem is the Javascript validator. If I define a class in one JS file in my project, then try to use it in another, it tells me that the type is undefined. This is really annoying as some of my scripts are littered with red squigglys.

Another problem is that this code:

```
var m_dialogFrame = document.getElementById(m_dialogId);

```

Makes a yellow squiggle saying "Type mismatch: cannot convert from Element to \_\_\_m\_dialogBody5" I can fix it by adding

```
    /**
     * @type Element
     */

```

Before it, but that, also, will be messy.

Also, both:

```
new XMLHttpRequest();

```

And

```
new ActiveXObject("Microsoft.XMLHTTP");

```

Get red squiggles saying "x cannot be resolved to a type"

The last problem is with:

if (m\_options.width != "auto")

Gets a red squiggly because: "The operator != is undefined for the argument type(s) Number, String"

How can I fix these issues, or just scrap the entire Javascript validation tool? BTW: it looks frikin awesome if I can get it to work.

Answer: 
Looks like this problem is due to the default browser for Eclipse not having the required libraries.

Try below steps to add the required library:
Project -> Properties -> JavaScript -> JavaScript Libraries -> Libraries(tab) -> Add Runtime Library -> select 'Internet Explorer Library'

This should resolve the issue. It did for me.
I found that old validation errors will stick around in the problems view and highlighted in the files until after you tell it to validate again, so after saving your JSP validation preferences, right click on a project to validate everything in it; that will make the errors go away.