This guide covers on how to use Actor. But the second option i gave you is much easier than dealing with actor.
Get an existing weapon sprite from the male class. For example: The normal sword sprite.
Using SPR Conview, convert the sprite into BMP. Click here to get SPR Conview
Take your custom weapon sprite and do the same in a different folder.
Now you have to match the positioning of the sword on your custom weapon bmps with the bmps from the normal sword sprite.
Once you are done with all the frames, re-build the sprite using SPR conview > Convert BMP into Sprite.
As for the act, take the act from the normal sword sprite and re-name it to your custom.
If the positioning looks the same to you on your sprite and the official, just take the act from the official weapon sprite and you don't even have to go through the above.