We've got a customer, actually a decent friend of mine too, who is getting plesk (one of those all-in-one hosting management tools). Except because he uses frontpage, he needs an older version of Plesk.
I get to installing it, and the installer complains "you have perl 5.008006 installed, you need perl 5.008007".
I try looking for perl 5.8.7 -- the current version is 5.8.8, and the one that came with the OS is 5.8.6. For a VERY SHORT while there was a 5.8.7 available. The installer doesn't like 5.8.8 (grr!!).
I try modifying the installer -- to tell it "you want 5.8.8". No good. The installer has an embedded checksum -- and it breaks my head as to how to even CREATE a file that has an embedded checksum, since changing the checksum CHANGES THE FILE, and thus CHANGES THE CHECKSUM.
I look on the FreeBSD archive mirror (where old releases are kept in their entirety (linux could learn something from this)) -- and I find a perl 5.8.7 tarball here:
Except that when I install it, it dies a horrible death because it's a 6.0 package, and doesn't have the right library links.
Okay, fine. Cracks Knuckles
I go cruising through the FreeBSD cvsweb repository, find the exact date that things got upped from 5.8.7 to 5.8.8, then I unleash this:
cvs co -D '12/23/2005' ports/lang/perl5.8
cvs server: Updating ports/lang/perl5.8
cvs server: Updating ports/lang/perl5.8/files
Oh, Hello, Newman. I cd into the directory, build, kill of any previous versions, and install.
I take somewhat pride in the fact that nobody else, period, could have done this. We've got one other tech with possibly the skill, but there's more BSD-centric knowledge required.