I believe he refers to the pokemon 493 patch for pokemon diamond (U) (there were similar ones for the GBÂ and GBA games but given the section...:
Download
http://gbatemp.net/index.php?download=598 (I think I have an xdelta version on my site somewhere as well)
From the link above:
Comment by: thegame07 · Posted on: Sat, Aug 11 2007 3:22 am
some people are having trouble with this let me help....

1. extract the folder
2. click on the green tree icon
3. click on the top right botton
4. add your rom
5. click on the botton left button
6. after the message comes up the rom is now patched.
7. close the patcher
8. copy the rom onto the card
9. enjoy