Can get the following kind of error when trying unpack archive java software downloaded from the Sun website (http://java.sun.com/products/archive/):

# ./j2re-1_3_1_03-linux-i386-rpm.bin
…
Do you agree to the above license terms? [yes or no]
yes
Unpacking…
Checksumming…
1
The download file appears to be corrupted. Please refer
to the Troubleshooting section of the Installation
Instructions on the download page for more information.
Please do not attempt to install this archive file.

The solution is to set the following environment variable:

export _POSIX2_VERSION=199209