qemu hangs in windows 7 host with -serial pipe:windbg

Execution line:
qemu-system-i386.exe -m 512 c:\Disks\Qemu_XP_en.vhd  -serial pipe:windbg

It waits for the pipe.
Execute windbg
c:\WINDDK\7600.16385.1\Debuggers\windbg.exe -k com:pipe,port=\\.\pipe\windbg,resets=0,reconnect

GUI black screen shown. QEMU hangs.

qemu v1.5.3 (c0b1a7e207094dba0b37a892b41fe4cab3195e44). MinGW built.