Apple has released iMovie HD 5.0.2 update which addresses issues related to video and audio synchronization for DV projects and other issues. These include:
• Audio in PAL widescreen
• Sharing (exporting) HDV to videocamera tape
• Synchronizing with HDV 720p content
• Importing video from a DV videocamera when using analog passthrough or recording live video
• Compatibility with some analog-to-digital converter boxes
• Capturing video with Hi-8 (Digital 8) devices
• Placing titles over DV content
• Playing iPhoto slideshows that include protected content
• Opening iMovie 4 projects that use speed-adjusted clips.
More info and download link (2.7MB) here.