Comment 0 for bug 878354

Matthew Paul Thomas (mpt) wrote :

Third-party .deb packages -- such as Opera and Chrome -- sometimes have their data.tar portion compressed using LZMA.

Until Ubuntu 11.10 this wasn't a problem, because the lzma package was installed by default. In 11.10, however, it was not (bug 868188).
<http://my.opera.com/community/forums/topic.dml?id=1124872&t=1318873023&page=1#comment10564932>

To work around this problem, software-center 5.0.2 Recommends lzma.

However, as described by ruario in that bug report, "the lzma package installs the older lzma utils, which are no longer actively maintained[. T]he upstream maintainer of lzma utils is the same as xz utils. He considers xz to be the replacement for lzma, which is why it is backwards compatible".

So, apt should probably use xz-lzma, and software-center should no longer depend on lzma.