[plt-scheme] serial port in windows

Hello,

Does anyone know how to open serial port in windows.

I wrote a program which communicates with deivce connected to serial port
which works fine in linux , but when using in vista , it just crashes
i.e drscheme
crashes.

In linux i do: (open-input-output-file "/dev/ttyUSB0" #:mode 'binary
#:exists 'update) to
get input and output port for serial port and can read write with no problem.

In windows(vista) , i tried (open-input-output-file "\\\\.\\COM15"
#:mode 'binary #:exists 'update)
which though opens it , but when i try to read from it , drscheme crashes.

Thanks in advance.