[XeTeX] Hyphenation of compound words in XeTeX

[Bruno Voisin]

Hello,

I've just noticed that XeTeX seems to apply different rules for 
hyphenation of compounds words than standard TeX, so that 
small-amplitude may be hyphenated as (I selected British hyphenation)

small-amp-
litude

if required, which is nice. However, an unwanted side effect is that I 
just got half-plane hyphenated as

half--
plane

Is there something that can be done against this?

Bruno