Cygwin: Back up open files?

[Karsten Violka]

Dear rsync developers,

is there a solution to backup open files with rsync on windows? 
Microsoft provides a SDK for Volume Shadow Copies on XP and 2003, there 
is even a commandline tool to create snapshots for backups.

http://blogs.msdn.com/adioltean/archive/2005/01/05/346793.aspx

Could this be combined with the cygwin-version of rsync? I don't think 
cygwin can copy from a windows devicename like

\\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy253

best regards,

Karsten Violka
Staff Editor
c't Magazine