Hi I am trying to find an importer for blender 2.6 that can import .mdl files because of something that I'm currently working on.

mdl is a compiled format, there are no importer/exporters for it.

You need an mdl decompiler which will break it down into its component parts, then you may be able to import those into Blender.

example... .mdl files in Source decompile to .smd which you can then import with smd-tools.

Of course, when you are done, you will have to compile them back into .mdl to use them.
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