[lubuntu] does not look like a tar archive error

/usr/local/src# gunzip < /mnt/MySQL/Linux/tarballs/source/mysql-4.0.21.tar.gz | tar xf -

bash: /mnt/MySQL/Linux/tarballs/source/mysql-4.0.21.tar.gz: No such file or directory

tar: This does not look like a tar archive

tar: Exiting with failure status due to previous errors

could anyone please help me on dealing with the above error.