GNU screen (sparc64) - shells take no input

[vom513 <vom513%gmail.com@localhost>]

I have GNU screen on sparc + hppa - and it runs fine.  (Built by me from 2025Q3).

On sparc64 (I’ve tried two different machines) - screen starts up and ctrl-a screen mechanics work and display.  I can create and kill screens etc.

But the actual shells are “seized up”.  I get my prompt, but typing is a black hole.

Any idea what this could be ?