It is, at least in the version I usually play (Epyx release 1.49, I think).
The melee combat via TAB is actually a pretty neat idea.

So, I've now tried the game. Not enough to really formulate an opinion, admittedly, but I'm really liking it so far. The Lovecraft atmosphere is quite nice and the interface is rather user-friendly.
And this may be a small detail, but it's very interesting how different it feels to have all the game messages be in first person, I don't think many roguelikes do that, or at least not those I've played.

I have, and it's very good.

Do you know if it's possible to unload the weapons in Infra Arcana? I tried upper-case "G" but that didn't seem to work.

It seems you can only unload weapons via "G" if they're lying on the floor. I just tried it and had to drop my colt in order to unload it.

Ah, so that's how it works! Thanks for figuring it out! :)

But I hope that command could work with a wielded weapon in future versions! :P