Dear Nina and Johan,
from what I see, the story is from the Devadhamma Jaataka.
http://www.tipitaka.net/tipitaka/spectra/jataka
The prince's name is Mahisaasa. Hope that helps.
metta,
Yong Peng.
--- In Pali@yahoogroups.com, johan wijaya wrote:
However, if anyone had any information regarding to this, do share it.
> A friend of mine is currently translating the Jataka tales taken
> from Buddha's Tale for Young and Old Vol. 1(int. by Ven Kurunegoda
> Piyatissa). She's got a problem with translating the name(s),
> especially the name of Prince Goodspeaker, which is stated on
> Chapter 6 (page 22).