Click and shift+click both events to select them, right click and select Synchronize - by Moving or Synchronize - by Slipping.
From the online help file:
To restore synchronization, right-click the audio or video event you want to synchronize, choose Synchronize from the shortcut menu, and then choose a command from the submenu:
By Moving
Moves the event you clicked so it is synchronized to its corresponding audio or video event.
In the sample events above, the audio event would move to the left if you right-clicked it and chose Synchronize > By Moving.
If you right-clicked the video event and chose Synchronize > By Moving, it would move to the right.
By Slipping
Slips the contents of the event you clicked so the audio and video are synchronized. The events do not move, but the contents of the event you right-click are shifted forward or backward to restore synchronization.
For more information about slipping, see "Slipping and Sliding Events."
Hmm Excaliber looks nice.. although I didn't see where it would restore the sync. I may have missed it. Anyway, can't afford it right now. Wonder if there's a free/cheap alternative.