7.2 to 8.0 serial not working

[Wes Morgan]

I just upgraded from 7.2-stable to 8.0-stable, same kernel config (with 
uart), same everything else and now I can't receive more than a few bytes 
of data from my weather station before it just waits incessantly. 
Everything worked before, with the same serial port settings, uart device 
etc. Has anything else changed in the serial interface? I'm using the 
cuauX devices at 2400 baud.