resetting the DNS cache: OS X, Firefox

• OS X: How to reset the DNS cache
• Windows (Vista): http://en.kioskea.net/faq/10548-vista-reset-the-dns-cache
• https://addons.mozilla.org/en-US/firefox/addon/dns-cache/ – has usability issues according to the reviews
• http://www.techiecorner.com/225/how-to-disable-firefox-dns-cache/ – go for the manual approach:
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 This is the manual approach for Firefox:

• Introduce 2 new variables within about:config:
• network.dnsCacheExpiration (integer / 0)
• and network.dnsCacheEntries (integer / 0);
• my problem with this: if you want to reset these switches, that's fine with Firefox, just that they get their data types changed to "string"; and once, you want to set them again to "integer / 0", you simply can't; for the time being I just assume, Firefox doesn't seriously consider the data type and accepts "string" for these 2 as well.