In fixing bug 231453 (P2 doesn't install
all features) I either directly or indirectly changed the order that some
features were compiled, so the webservices code was being compiled before
the server code, and hence, not "finding" the classes it needed.
(In a development environment, there is no order effects, so the code all
seems correct there).
I've confirmed just fixing the order of
included features fixes the build problem (on a quick, local build) so
our official RC4 candidate should be ready about 8 AM Wednesday.