GNU screen---uses my login password on other distros, but not on Slackware.
 

On Red Hat, Fedora, and Gentoo, when I use GNU Screen's "C-a x" binding to lock the screen, it locks immediately, and will unlock if I use my account password.

On Slackware, however, it first prompts for a password twice and only then will lock. It also responds to this password rather than my system password.

Is there a way to use the behaviour of the Red Hats and Gentoo? (I have a feeling that this is a side effect of not using PAM.)

Nope

I just had a look at Pat's SlackBuild for it and he removes the SUID bit from screen to avoid any "issues" that may arise from that.

The SUID bit is required for screen to query the systems password database as only root can touch that part of the system.

You can SUID it yourself if your prepared to take the possible risks a simple "chmod u+s /usr/bin/screen" is all it takes.

Yup, that did it. I'll be setting it, as this box is my laptop and is locked down (no incoming connexions).

Thanks!