Você pode usar packages.ubuntu.com para isso.
Exemplo: o link no topo mostra Package: perl (5.14.2-6ubuntu2)
. O link mostra Package: perl (5.10.1-8ubuntu2.1)
.
Isso funciona para outros softwares também.
Você também pode pesquisar por perl e obter uma lista com todos os lançamentos, como: link
Isso mostrará:
hardy (perl): Larry Wall's Practical Extraction and Report Language
5.8.8-12ubuntu0.5 [security]: amd64 i386
hardy-updates (perl): Larry Wall's Practical Extraction and Report Language
5.8.8-12ubuntu0.5: amd64 i386
lucid (perl): Larry Wall's Practical Extraction and Report Language
5.10.1-8ubuntu2.1 [security]: amd64 i386
lucid-updates (perl): Larry Wall's Practical Extraction and Report Language
5.10.1-8ubuntu2.1: amd64 i386
oneiric (perl): Larry Wall's Practical Extraction and Report Language
5.12.4-4: amd64 i386
precise (perl): Larry Wall's Practical Extraction and Report Language
5.14.2-6ubuntu2: amd64 i386
precise-updates (perl): Larry Wall's Practical Extraction and Report Language
5.14.2-6ubuntu2.1: amd64 i386
quantal (perl): Larry Wall's Practical Extraction and Report Language
5.14.2-13: amd64 i386
raring (perl): Larry Wall's Practical Extraction and Report Language
5.14.2-14: amd64 i386