QuickTime 7.6.6 for Leopard is recommended for all QuickTime 7 users and according to Apple brings about "general reliability improvements for iMovie." Additionally, the update addresses a long list of security vulnerabilities related to maliciously crafted audio or movie files that could allow attackers to cause crashes or run arbitrary code. The update is available via Software Update or the Apple Support Downloads page. (Free, 68.63 MB)
Undelete an iPhone Voicemail Message
There's no Command-Z in the Phone app, but you may be able to retrieve a deleted voicemail message: Open the Voicemail screen in the Phone app. At the bottom of the screen, tap Deleted Messages. To restore a listed message, tap it and then click Undelete.