Documentation in Eclipse shows up as HTML

When I hover over a function, I get the documentation, but the HTML isn't being parsed. This happens to me in both Aptana 3 and Eclipse Helios. Any ideas? I'm clueless. Ubuntu 1开发者_如何学C1.04 btw

EDIT: When I press F2 for focus, the dialog turns yellow and the content is

<div class="header"PHP API
require_once
The require_once keyword

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First, make sure you have Internal Web Browser available in your Eclipse. For this use menu Window/Show View/Other/Internal Web Browser. If browser is not available, read SWT FAQ: What do I need to run the SWT Browser inside Eclipse on Linux?

Cheers, Max