Many thanks for your response Ludovic, I was unaware of the libGlade->GtkBuilder migration changes since I last used Glade, hence my knowledge of this is limited (for now).
Your point regarding the package dependency on Glade from Ada libraries is well made - I concur.
Though, I must admit some remaining minor confusion over exactly which tools are required?
It's my understanding that the GtkAda bindings are to Gtk 2.24?
In this recent item: http://lists.ximian.com/pipermail/glade-devel/2011-October/001910.html
it states that to target Gtk+ 2.24, version 3.8.1 of Glade is required: this statement leads me to think this may be a separate issue from the new GtkBuilder preference (over the now deprecated libGlade) of the GtkAda libraries, because GtkBuilder is included with Gtk 2.24.
As that link shows, there is some reason that Glade 3.8.1 is (I assume) still needed for working with Gtk 2.nn dependant code, though I'd admit a high degree of ignorance of the exact reasons at this time.
However, given that the developers of GTK's Glade provide both version 3.8.1 and 3.10.2 concurrently for some reason, I am still doubting the wisdom of removing the 3.8.n series of Glade from the Debian package sources.
So, if anyone is able to answer the following questions they may shed some light:
Does the output of the Gtk3-only Glade 3.10.1 work okay with the GtkBuilder in Gtk version 2.24?
Or is Glade 3.8.1 still needed to support older UI designs and folks that have to work with them?
What of interfaces that still require use of older widgets?
Is the difference between the two version's XML outputs limited to removed and added widget classes availability, or are other event / globals changes apparent between Gtk 2.24 and Gtk 3.nn that will lead to interoperability problems?
i.e. IF Glade 3.10.1 output XML will work correctly with GTK+2.24, then it's usage would be preferred, so to encourage the dropping of deprecated or removed widgets, and the uptake of newer widgets. IF this is the case, great news, I will be installing 3.10.1 for new development work and I need worry no further; but the removal of Glade 3.8.n series will not be good for anyone having to maintain or extend older code..?