I'm currently taking an introductory OSA class. The Sabaen Dictionary by
Beeston Ghul Ryckmans and Muller references the cognate under 'l (an d'lh
refers back to it) but lists 'lh as an alternate form, 'l'lt as the m.pl.
I don't know anything about the geographic or diachronic differences in form,
so I can't be any help there. We did read a text today with 'lh in it, and
Gene
Gragg, the prof. didn't point out anythign unusual about it, so I'm guessing
that the two forms are about equally used.
--
Ben Spackman
"In theory, there is no difference between theory and practice. But,
in practice, there is."
- Jan L.A. van de Snepscheut