slime + chokes on temporary-file-directory set to "~/temp" on Windows

I am running Windows versions Emacs and CLISP. If I have temporary-file-directory set to "~/temp", slime loading will report ;; Loaded file C:\Users\977315\documents\.slime\fasl\2013-09-29\clisp-2.49-windows-x86\swank.fas ... *** - OPEN: Directory #P"C:\\Users\\...\\documents\\.emacs.d\\~\\temp\\" does not exist I set temporary-file-directory to an absolute path, such as ""c:/Users/.../AppData/Local/Temp/" slime loads OK. I grepped slime's lisp files for temporary-file-directory, but did not see it. I tested this with clisp -norc option. Is this a bug - since on Windows Emacs accepts `~' for the home directory? Thanks, Mirko