It's been a while since I've done it; but yes that's certainly do-able.
Here's the configuration I used - assuming an inside interface nameif "inside" and, of course, substitute your own values for the bracketed ones below:
object-group network inside_networks
network-object <subnet a, mask>
network-object <subnet b, mask>
access-list inside_networks extended permit ip object-group inside_networks any
access-list Bluecoat extended permit ip host <bluecoat proxyaddress> any
wccp 1 redirect-list inside_networks group-list Bluecoat password <password>
wccp interface inside 1 redirect in