Bonjour Sleep Proxy protocol documentation?

Can anyone point me to a technical description of the Bonjour Sleep Proxy protocol description, or a technical description of how it works?
(I've already seen the Apple KB article http://support.apple.com/kb/HT3774
providing an overview of the "Wake on Demand" feature, the reference
to "Sleep Proxy Servers" in http://files.multicastdns.org/draft-cheshire-dnsext-multicastdns.txt , and the Sleep Proxy Service patent in http://patft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u= %2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=7,330,986.PN.&OS=PN/7,330,986&RS =PN/7,330,986 .)
What I'm really trying to understand is if the Sleep Proxy server is intended to take over the IP address belonging to the sleeping device. Based on the documents above, I gather that the Sleep Proxy server may respond to mDNS queries for services registered by the sleeping device. But I'd guess the mDNS responses come from an IP source address of the Sleep Proxy Server. I wouldn't expect the Sleep Proxy server to start sending IP datagrams using the IP source address of the sleeping client, or to respond to ARP Requests targetting the sleeping client's IP address. But lacking a technical description of the Sleep Proxy Server is expected to behave, I'm just guessing.
I ask because starting on September 3 2009, I've seen three Apple Time Capsules "steal" IP addresses belonging to other devices. (For several hours, the Time Capsule's uplink sent ARP Reply packets for an IP address that didn't belong to it. It did so at the same time it send ARP Reply packets for the Time Capsule's assigned IP address.) The victim of each IP address theft was a Macintosh computer that had no apparent relationship with the Time Capsule. The release of the Sleep Proxy client software in Mac OX X 10.6 several days earlier makes me wonder if Sleep Proxy service is the cause of these IP address thefts.

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