My client using webobjects 4.5(one of the last versions that supports Objective-C) on backend. And I need to develop using this framework. Problem is that I'm using Ubuntu linux I've tried to found how I can install framework on my OS, but found only WO 5.4 What can you advise? How I can install WO 4.5 On ubuntu?
P.S. Found GnuStep project. Is it fully compatible alternative to WO 4.5?
Since the Objective C runtime has never been ported to Ubuntu, and there is no reason for Apple to ever do this, one cannot run WO 4.5 on a Linux distro. I think it actually was shipped to also run on Windows NT and on HP/UX and Solaris, but these probably will not help you either.
I am not sure if you can use the GnuStep code for any commercial work. I would be surprised if any lawyer would ever sign off on its use. But YMMV.
Sorry, but there does not seem to be any good news for you.