According to this recent edit to Kappei-sama's Japanese Wikipedia article suggests he had at least a small role in the Mezon Ikkoku anime.In case it wasn't a vandal edit(unlikely since it was by a register user),hopefully it was before Ibuki Yagami was introduced(or it least in an episode without that character)for obvious reasons...

Happy birthday to Shigeharu Matsuda(who turns 57)and Youko Teppouzuka(who turns 45)...