0444d588_18_FeatureList___FedoraProject__Summary
[% Complete] 100% [Name] Virt Guest Suspend/Hibernate support [Updated] 2012-08-07 [Summary] 
Linux guests don't do S3/S4 properly right now due to missing functionality in the virtio layer to save state before hibernation and restore it after resume. The plan is to extend virtio and individual virtio drivers to handle hibernation, as well as userspace components like libvirt + qemu to enable everything.
Releases/18/FeatureList - FedoraProject