With this release, sessions can be configured to not auto-start by adding a [Yawp] group 'session_start = false' directive and commenting out the [Auth] group, per request by David Glenn. Download the new version from phpyawp.com.
Also, I'm beginning work on Yawp2, which should be infinitely more configurable using a plugin architecture (suggested via proof-of-concept code from Ian Eure). Instead of being limited to the standard Yawp object set (Auth, Benchmark_Timer, Cache_Lite, DB, Log, and Var_Dump) you will be able to plug in any PEAR object and lazy-load it on first call, as well as autoload objects at Yawp::start() time (the current behavior). There will be support for convenience methods through the core Yawp object so that you can use method calls to a plugin without having to load the plugin yourself.
The idea behind Yawp is that you always need a certain set of single objects in your app: a database connection, a cache, authentication, a logger, and so on. Yawp instantiates, aggregates, and encapsulates those objects away from the global space so you can concentrate on the "real" part of your program. Does that mean Yawp is an example of aspect-oriented programming?