System: Windows 7 64 bit - SBCL (32 bit)
after a fresh install i do M-x slime and it compiles some code and when comes to connect swank it enters a loop of errors and at least it stops.
the first error message is "The function SWANK-BACKEND::FD-STREAM-INPUT-BUFFER-EMPTY-P is undefined."
(my quicklisp installation was working without any problems before)
SLIME was recently updated. Have you raised this issue on the SLIME mailing list?