How to use package from old version?

[Tom_Peters]

Hi,
I started using a XUbuntu workstation, "trusty" release 14.04, and am trying to compile an old but indispensible X11/Motif application written in C (XInvest) that I have been dragging along for decades.
It requires, among other things, the PrintShell extensions to Motif (Xm/Print.h). These come in libmotif-dev and dependencies.
http://packages.ubuntu.com/trusty/libmotif-dev
The Print.h from that package dates from 1996. However the XInvest program uses some constructions that, interpreting from what I see on another system, were available in Lesstif from 2004. But the lesstif2-dev package existed within Ubuntu up to "precise" but not in "trusty" anymore.
http://packages.ubuntu.com/precise/lesstif2-dev

So how do I go about installing Lesstif on "trusty"?

It has been 10 years since I had a Linux workstation so I am not familiar with the do's and don'ts in modern package management with Ubuntu.

Thanx for any advise,
Tom

[Tom_Peters]

Hi,
I installed XUbuntu 14.04 "trusty".
Now for compiling some old X11/Motif C program I need the Motif libs as wel as the development header files.
Trusty offers libmotif-dev (http://packages.ubuntu.com/trusty/libmotif-dev (http://packages.ubuntu.com/trusty/libmotif-dev)). However the Xm/Print.h is very old (1996) and obsolete.
On my previous computer I used Lesstif, with a header file dating from 2004 that worked there.
But Lesstif is not in trusty. It used to be in "precise" (http://packages.ubuntu.com/precise/lesstif2-dev (http://packages.ubuntu.com/precise/lesstif2-dev)).

So my question:
Can I install packages from "precise" on my "trusty" system?
How? http://ubuntuforums.org/showthread.php?t=2223607 suggests that it is difficult or impossible to downgrade a package to a previous version.
Also I foresee complications. I suppose I'll have to remove libmotif - but that might force removing any application packages that depend on it. But if I try install lesstif2-dev next to libmotif then it will overwrite the files (like Xm/Print.h) that are also in the libmotif packages.

[bapoumba]

I have merged your two threads. Have you had any success with the suggestion there ?
https://answers.launchpad.net/ubuntu/+source/motif/+question/261920