rsync - Dec 2008 - pre-exec works in XP but not in Vista

I run a sshd as well as a rsyncd within cygwin in both, in WindowsXP as well
as in Windows Vista.
Strange to say, pre-xfer will work in XP perfectly but in Vista only after a
previously login through sshd.
Strange too, that sshd use bash.exe and pre-xfer use sh.exe which is a copy
of bash.exe.
Without a previously login through sshd the forked rsync process will hang.
If I do remove sh.exe, rsync will log an error (256). But if sh.exe is in
place rsync will hang. Wait for sh.exe?

Werfault.exe is running, I believe to report the following error, which I
found in "Control Panel->System and Maintenance->Problem
Reports":
Produkt
sh.exe

Problem
Funktioniert nicht mehr (=doesn't work any more)

Datum
29.12.2008 15:00

Status
Nicht berichtet (=not reported to Microsoft ;-))

Problemsignatur
Problemereignisame:     APPCRASH
Anwendungsname: sh.exe
Anwendungsversion:      0.0.0.0
Anwendungszeitstempel:  48a031a0        (=Application timestamp)
Fehlermodulname:        StackHash_e51a  (=error module name)
Fehlermodulversion:     0.0.0.0
Fehlermodulzeitstempel: 00000000
Ausnahmecode:   c0000005                (=exception code)
Ausnahmeoffset: 00000000                (=exception offset)
Betriebsystemversion:   6.0.6001.2.1.0.768.2
Gebietsschema-ID:       3079
Zusatzinformation 1:    e51a            (=additional informations)
Zusatzinformation 2:    4c0d4d78887f76d971d5d00f1f20a433
Zusatzinformation 3:    e51a
Zusatzinformation 4:    4c0d4d78887f76d971d5d00f1f20a433

Thanks for any hint and a happy new year!
Matthias
-- 
Don't Panic