anyone ever heard of an adjustable cup on a bottom bracket cup being really difficult to tighten up and basically stops turning before it reaches a solid adjustment?

Have you checked the obvious things?

Is the cup mis-threaded/cross threaded?
Is the BB the right size for the BB shell?

yeah...i have had the same frame for about 8 years now and it progressivly gets harder and arder to the point that it may be un rideable. the crappy thing is its ALREADY italian threaded so no retapping. initially thats what i wondered if it was originally english, retapped italian and then the italian cup was a hair to big. i dont know. its a real bummer. i have never heard of anythig like this. even sheldon is at a loss.

Well if its English retapped as Italian won't the BB size be 68mm, where as an Italian BB shell is 70mm hence the difficulty of getting an Italian BB to sit in this shell? Could that have anything to do with it?

Should be easier enough to measure the BB shell, which should tell you whether its really Italian or an english BB shell masquerading as Italian. That should at least remove some of the confusion.

Other options:
You could always get the threads chased to clean 'em up.
Get busy with a toothbrush and some cleaner on the threads to flush out all the dirt.

Obviously its very hard to diagnose these kinds of things with just text. Sorry I can't be of more help.

Maybe your shell threading is gunked up with corrosion or solidified grease. I would start by going in there with some degreaser or kerosene and a toothbrush or (better yet) a small brass-bristled brush (look at harbor freight to find these for cheeeeep). Once you scrup some gunk out of the threads and get them nice and shiny again, do the same to the threads on the cup and see if it goes together any easier. It would be wise to put some fresh grease on the threads before reassembling the final time so you don't have corrosion or seizing problems the next time you need to take it apart.

If that doesn't work, you probably need to get the threads chased. Maybe your shell is slightly ovalized or has a slight dent or something that would cause the cup to not want to thread in. Retapping the threads with the proper tool should at least partially correct this problem to the point that you can adjust the cup without a cheater bar.

The first things that jumped in my my mind are: The theads are stopping it or the bearings/races are stopping it. These are both fairly easy to check for though.

Try screwing in the cup without the spindle or bearings. Does it go in any further than when you try to install everything? If so, the spindle/bearings are your problem. If not, it's the threads. Maybe this will help with the diagnosis?

thanks alot for your help. all this gives me a little more enthusiasm that all is not lost for my frame.

yup. happened to me before.
after chasing the threads BB went in fine.

awesome. i feel good now. pretty pretty pretty pretty good.