Well, I like Suikoden as well as the next person, but my question is still about the "gold-for-XP" translation. If it's about increasing the sharpness or usability of a weapon, that's not a problem, because in my own engine I have considered something of this nature (I'm on the fence about implementation though).
But in reply to Venka's link, which points to a script to give equipment "experience", Mitch0 didn't indicate that wasn't the intended implementation, but rather that this script didn't work because of perhaps incompatibility. I assume then that Mitch0 wants a scripted system related to the XP-based leveling of an item or weapon.
(In such cases, this isn't so much of a "cheat" as it is just feeling that the player wants to get to max equipment level faster through paying to accelerate the item's experience/level. -- Isn't this possible that it could invalidate or even break some games' designs? Most game designers make the battles in their games to somewhat increase in level and difficulty as the player-party experiences the adventure.)