`zmacs regions' & pending delete

One of the things I use a lot in XEmacs is the pending delete feature,
which means that if the region is active (highighted) then any key
which would insert a character first deletes the region.

It looks like this is supported in LW if the editor is emulating
Windows editors, but I couldn't work out how to get it to work
separately from that.  Is it possible?

Thanks

--tim