Using uEye Cameras in an Extension on a 64-bit machine

I'm working on a project where we're using an [IDS uEye][1] machine vision camera. I wrote an extension that's supposed to read the camera and report back to Unity. Using DependencyWalker, I see that it's dependent on ueye_api.dll. Because I'm on a 64-bit machine, there's no such dll, but there is a ueye_api_64.dll. I put ueye_api_64.dll in the Assets/Plugins folder, and in the C:\Program Files (x86)\Unity\Editor folder, but I'm still getting the DLLNotFoundException. Has anybody used this or a similar camera before? Any help would be appreciated. [1]: http://www.ids-imaging.com/