Need help selecting DB for PC/Novell/Vax/Unix/HP3k/HP1k

I need some help as the last time I developed a serious database system was over five years ago and have not kept up with the awesome developments that have happened since then.

I'm in the midst of specifying a client-server Database for a bunch of different platforms. Our main client is a PC with Novell client s/w with telnet capability. However we must also support HP 1000 & 3000 terminals, and be able to share files with Apollos and Vaxes. We are developing a documentation vault for source code, internal procedures, etc. The existing vault is HP1000/HP3000 based. But it's 15 years old and we want to start from scratch.

My Platform block diagram looks like:

PC/Novell      Vax      Vax Terminal     HP1k/3k terminal     Apollo
    |           |           |                   |                |
    --------------------------------------------------------------
	Ethernet            |
                         Black Box
          (database with query & file transfer support)

My requirements are:
	Selections be based on industry standards
	To minimize system/code development effort
	Modularity and non-proprietary protocols, etc.
	Only move query results across ethernet backbone

What I'm thinking of for the Black Box is:
	An SQL engine of some sort (Oracle/Novell SQL/?)
	Have the client software maximized for use on PC (SQL based)
	Use ftp to transfer files to/from db server, vax, u*x, hp
	Thinking of C or C++ for non-db related code so the db lang. should
	   have an engine or hooks for c or c++
	Using a PC with a Telnet daemon to take care of non-PC clients
           or potentially have portable code for non-PC hosts
	Leaning towards Paradox for client software due to in-house exp.

I'm hoping that I can get some input from developers/vendors/anyone knowledgable as to what people are developing in now, pitfalls to watch out for, lessons learned, things you wish you hadn't done, things you wish you had done. Any comments on what I've said.  

Please reply directly to tymann_at_ops1.bwi.wec.com - I've posted this to several news groups. I will compile all info I receive and make a post if it looks like it will be helpful.

Thanks,
John Tymann

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