Connecting Cisco phones into an Asterisk environment

I have a customer who is looking to move to the Asterisk platform, but he has all Cisco IP phones. While reading up I saw that the supported protocols include SCCP --skinny. I know that this is a relatively new thing, and I am wondering what the best way to integrate the skinny protocol into their asterisk network is.

Is it best to place some type of firm ware onto his phones or is there something you can do to the Asterisk box so that it can translate the skinny?

Any suggestions would be greatly appreciated.

Just a check, the phones are SCCP or SIP? A lot of Cisco phones can be either. I have used the asterisk skinny, the SCCP branch (I think only available for 1.2) and SIP. SIP is the easiest (mostly because I am used to it), but the others seem to work OK. Converting Cisco phones from SCCP to SIP is an irritatingly tedious process and you either buy the firmware from Cisco or well… you know what I mean.