According to Document ID: 2654HQ
Eudora should continue to work just fine on the new Tiger OS.
We are excited about the new technologies in MacOSX Tiger, including SpotLight and WebKit HTML display/authoring. We are currently reworking Eudora to take advantage of these technologies, as well as converting it from Carbon to Cocoa, to take advantage of Cocoa’s status as Apple’s preferred environment.
These changes will take considerable time, but we know you will be very pleased with the results, and ask for your patience while the work is being done. We’ve not yet determined the exact release date for this retooled version of Eudora, but anticipate Fall 05 timeframe.
[Via: MyAppleMenu ]