Hi odometer, thanks for the clarification. Daylight Savings Time is a bit more precise description than "civil" time. Implementing it should be easy.
Implementing auto-leap-second insertion as you stated earlier should be more difficult for the reasons I outlined above.
Looking over the schematic, I see that the Evil Mad Science alpha clock does not seem to have an connection from the SQW output from the Chronodot to one of the 644 hardware interrupts. Oh well, there goes that great idea.
IMO, no library is needed to access all the data in the Chronodot. Implementing the I2Ccode is pretty simple, gives you a great appreciation for bit shifting and other operations to assemble the various pieces of data.
Best of luck with your project.