DNS Caching

I am having some trouble understanding the operation and configuration of DNS caching on a CE.
Does the listener command intercept the CE's DNS requests that would normally go to the nameserver configured with the "ip name-server" command(s) and send them to the name or address used in the listener command?
What does this mean: " The DNS server must know the DNS name of the host on which it is being enabled and map it to an IP address within its own cache."? I can't tell if the DNS server referenced is the CE.
Also, is it more common to limit the cache size on the smaller end of the scale or the upper end?
Thanks.

"dns listen" command has to be configured with the name and ip address of your dns server. You can use the "dns pin" command to do this.
http://www.cisco.com/univercd/cc/td/doc/product/webscale/uce/acns50/cref50/14623ref.htm#2408858
DNS-caching on the CE is not a "caching dns server". It is only for the CE to use itself - and not to point the PC's "dns server" at. DNS is only needed in Proxy mode.

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