Now here's a question I'd like to see answered too.

I'm getting the same error, but here's some more details:

I am deploying a war to "server/default/deploy".

In jboss-web.xml, I have the line:

<context-root>/vdq</context-root>

I have a page in the following structure in the war - "[context-root]/managers/mgr.jsp"

In the html of that page is the link for the css style sheet:

<link href="/styles/general.css" rel="stylesheet" type="text/css">

So to recap, the site root of my war file should be "/vdq", meaning that even though my jsp page is in /vdq/managers/mgr.jsp, it should consider it's position to be in "/managers/mgr.jsp", which would allow it's css link to find the style sheet at "/styles/general.css", which actually lives at "/vdq/styles/general.css".

When I access the page however, the style sheet is not found, and the following line shows up in JBoss's error log:

MAPPING configuration error for request URI /styles/general.css

This error message is repeated every time the page is accessed.

In addition, when JBoss boots, I get the following several times:

MAPPING configuration error for request URI /

If I've missing something blatently obvious here, I wouldn't mind someone answering this even if it makes me look like an idiot. Learning is always painful. Besides, I've seen this problem all over the 'net with no good answer, and I'm sure others here would appreciate a hard list of how and why this happens and how to fix it.

This is in response to the stylesheet URL question, not the MAPPING configuration error at boot time.

The HTML tag

<link href="/styles/general.css" rel="stylesheet" type="text/css">

is only interpreted by the browser; it is not server side code. The browser knows nothing about context paths or war files or even the existence of the Servlet API; it just sees a URL which it has no choice but to interpret as relative to the server root.

If you output a URL, you need to include the context path in the URL. Helping to manage this kind of plumbing work is one of the main benefits of using taglibs (e.g the Struts html taglib and its html:link tag).