This article is from the Final-Fantasy and other Square Soft Games FAQ, by firstname.lastname@example.org (Nick Zitzmann) with numerous contributions by others.
Easytype version: What you're seeing is a bug.
Original version: This isn't a bug; this is a chance to waste a Golden
In the non-easytype version of this game, as well as the PSX versions,
there's a needle item which could revive characters who were turned to
stone if used, known as the "Golden Needle." If you had a needle and
tried to use it on Palom/Porom, you'd get a message which said: "No
effect. They have been turned to stone by their own will." The party
would then lose the needle.
The needle was taken out of the easytype version of the game, but the
item selector box would still appear if you talked to Palom or Porom.
And no, you can't unstone Palom and/or Porom at any point in either the
original or easytype versions of the game.