under Viper, I can do standard search and replace operations the VI way
without any problem (%s/bli bla/BLA BLI/) except when you want to
replace by the word SET followed by a space: %s/bli bla/SET / : as soon
as you type the space, the command gets executed and it is not possible
to add anything there after. I am using Xemacs 21.1.8.