Hi Yj,
You certainly shouldn't have to install LLBLGEN on to your production server. You will always need to deploy the core runtime library 'SD.LLBLGen.Pro.ORMSupportClasses.NET20.dll and any DQE depending on your back end database, which in your case should be SD.LLBLGen.Pro.DQE.Oracle10g.NET20.dll
The assembly has to be accessible using the many .NET binding rules e.g. in the GAC, in the same folder, or in another location using the codeBase binding element.
If your still stuck then use the assembly binding fusion log viewer and obtain a binding log when the assembly fails to load. This is very helpful and will tell you the calling assembly, and the assemlby being probed for, including all locations probed.
Cheers
Matt