Normally in Xemacs one can set the behaviour of the Delete key so that, if any text is selected, it deletes the text. You can set/unset this via a checkbox in "Options|Keyboard and Mouse". I believe this is what the Xemacs authors call "pending-delete-mode". However the xemacs which I got from doing an "emerge xemacs" the "Delete Key Deletes Selection" option is greyed out. I have spent quite some time Googling about trying to work out if it's a configuration thing, but the ways suggested to turn it on don't and I now suspect it's down to the way Xemacs is being built. Any chance this could be changed? Reproducible: Always Steps to Reproduce:
After yet more Googling this morning I discovered a reference to the package app-xemacs/pc and emerging this has enabled "Delete Key Deletes Selection", so my problem is resolved. Personally I'd put this into the main xemacs package by default but YMMV so I'll leave you to decide whether to leave this open as an enhancement request.
I'll follow upstreams's policy on this, and their policy is to distribute the app-xemacs/pc package separately. I won't make it a dependency of the app-editor/xemacs package. In any case thanks for the report and the later resolution.