Redwood Shores-based Oracle announced this morning that it has agreed to acquire Nimbula, a venture backed provider of private cloud infrastructure management software. Financial terms of the buy were not disclosed. Nimbula was venture backed by Sequoia Capital and Accel Partners, and headed by Chris Pinkham. Pinkham was formerly VP of Engineering at Amazon.com. Nimbula's software is used for developing infrastructure-as-a-service, public, private, and hybrid clouds.