[TYPO3] Full Backup on beta3

[Andreas Koppa]

Hello,

Have problems with Full Backup 0.9.1 and Typo3 4.0 beta3 on my Windows local 
machine.

Full Backup ends with a warning: 
Warning: unlink(C:/xampplite/htdocs/typo3temp/w4x/localhost-2006-02-26-512ee4b99fd84ce5bd73.tar) 
[function.unlink]: No such file or directory in C:\xampplite\htdocs\typo3conf\ext\w4x_backup\mod1\index.php 
on line 59

My Apache error-log shows two errors:
"whoami" unknown internal or external command...
"C:\Program" unknown as internal or external command...

Have done everything I could think of.  No way.

Any idea?
Thanks