The BundleContext.installBundle call only allows a single bundle to be installed at a time, unfortunately there's no hook point that dm Server can use to also install all of the bundle's dependencies.
If you'd like to continue installing your bundle(s) programatically and have the missing dependencies installed from the repository as well you can use dm Server's deployer instead of BundleContext.install(). The deployer's available to you as an MBean or as an OSGi service published under the com.springsource.kernel.deployer.core.ApplicationD eployer interface.
One word of caution: it isn't guaranteed that the MBean or the ApplicationDeployer interface will be unchanged in the run-up to the release of 2.0. It's unlikely that they will change but it is still a possibility.