Firefox 1.5 and "friendly" error pages (and how to disable them)

Firefox 1.5 has rather few new features, on of them are friendly error pages. So instead of a modal error window, a "friendy" error message appears as a page in the browser, for instance when the connection to a server times out.
Here is my take on that: Friendly error pages suck. Some part of this sucking may come from the implementation of this technique in Internet Explorer (I could rant for hours about bugs in this particular area), but generally, I do not like the contents of the current page replaced by a browser-generated error message. (Consider, for instance, an online ticket site that is under heavy load.)
Anyway, there is a cure of course. Start Firefox, type about:config in the address bar and set the property browser.xul.error_pages.enabled to false, and your browser is healed. By the way, if you really like "friendly error pages" and you are still using Firefox 1.0.7, browser.xul.error_pages.enabled already exists there. A discussion of this can be found in Bugzilla.