Preparing to unpack .../mythes-en-au_2.1-5.4_all.deb ...
Unpacking mythes-en-au (2.1-5.4) over (2.1-5.3ubuntu1) ...
dpkg-deb (subprocess): decompressing archive member: internal gzip read error: '<fd:4>: incorrect data check'
dpkg-deb: error: subprocess <decompress> returned error exit status 2
dpkg: error processing archive /var/cache/apt/archives/mythes-en-au_2.1-5.4_all.deb (--unpack):
 cannot copy extracted data for './usr/share/doc/mythes-en-au/copyright' to '/usr/share/doc/mythes-en-au/copyright.dpkg-new': unexpected end of file or stream