There is an inconsistency in the way backwards-compatibility packages are named. Some (for example, compat-gcc and kde1-compat) have compat in their names and some just have a number. IMHO, it's much better to use compat since that would allow one to easily identify all the compat packages installed and remove them once they are longer needed. IMHO, it would be better if readline41 would be renamed into readline41-compat
Same reasons as 59574