rpm2tgz - .rpm is not an RPM

Hi.

I am not able to convert ALT Linux RPM packages to txz packages
http://ftp.altlinux.org/pub/distribu...lt1.x86_64.rpm
http://ftp.altlinux.org/pub/distribu...lt1.x86_64.rpm

Code:# file libpackagekit-glib-1.2.2-alt1.x86_64.rpm
libpackagekit-glib-1.2.2-alt1.x86_64.rpm: RPM v3.0 bin i386/x86_64

# file -i libpackagekit-glib-1.2.2-alt1.x86_64.rpm
libpackagekit-glib-1.2.2-alt1.x86_64.rpm: application/x-rpm; charset=binary

# rpm2tgz libpackagekit-glib-1.2.2-alt1.x86_64.rpm libpackagekit-glib-1.2.2-alt1.x86_64.txz
ERROR: rpm2cpio failed. (maybe libpackagekit-glib-1.2.2-alt1.x86_64.rpm is not an RPM?)
ERROR: rpm2cpio failed. (maybe libpackagekit-glib-1.2.2-alt1.x86_64.txz is not an RPM?)

# for i in `find . -type f | fgrep .rpm | sort`; do rpm2cpio $i | cpio -idmv &>/dev/null; done
error: ./libpackagekit-glib-1.2.2-alt1.x86_64.rpm: invalid signature tag Archivesize (1046)
error reading header from packageAnybody able to do this?

Thanks.