Buildcraft is in there, just double checked mods folder. denLib is also there, but in the coremods folder (as the instructions said). If this helps in knowing what went wrong, I copied the mods, coremods, and config folder from a working client .minecraft folder.
My friend and I are attempting to run a server with Forge, and I installed forge into the minecraft_server.jar. I also put all the mods we had into the mods folder, put the coremods in the coremods folder, and I'm getting this crash when I try to start up the server http://pastebin.com/BU1sx49W Any help is appreciated, thanks!