caching downloaded packages

[Mikus Grinbergs]

Smart 0.50, 64-bit SuSE 10.0.

Doing a 'smart upgrade', I see the message:  error - unpacking of
archive failed on file /usr/lib64/xulrunner-1.8.1;  cpio: rename
failed - Resource temporarily unavailable

If I repeat the 'smart upgrade' it downloads the file again (before
hitting that same error).  How come the downloaded file is not being
left in /var/lib/smart/packages ?

mikus