mozilla firefox do dns caching?

[Walter Tautz]

Does Firefox (in Hoary) use Dns caching? Looking into about:config
shows no variables whereas a google search suggests that the mozilla
browser does? The reason I ask is that I've noticed firefox telling
me it's doing lookups of hosts it just went to a few minutes before?
Now I've only noticed this because I think my sympatico.ca nameservers
in the waterloo, ontario region seem to be slow....

Can anyone enlighten me on firefox and dns caching?

Is there a lightweight dns caching name server I can install on my
machine?