I'm trying to do a request-reply message packet. I knew how to construct them, but I have no clue about how the reply mechanism works. I just don't know how I would react to a reply from the packet sending code. Can someone enlighten me please?
The same was happening to me
See this page in the wiki, it helped me at least:
http://www.minecraftforge.net/wiki/Eclipse#Fixing_textures_not_being_copied
If you are using Eclipse, see this page in the wiki:
http://www.minecraftforge.net/wiki/Eclipse#Fixing_textures_not_being_copied
Edit: I have edited the page for 1.6.1