Ribet [Ri] has generalized the conjecture of Shimura-Taniyama-Weil to abeli
an varieties defined over Q, giving rise to the study of abelian varieties
of GL(2)-type. In this context, all curves over Q of genus one have Jacobia
n variety of GL(2)-type. Our aim in this paper is to begin with the analysi
s of which curves of genus 2 have Jacobian variety of GL(2)-type. To this e
nd, we restrict our attention to curves with rational Rosenhain model and n
on-abelian automorphism group, and use the embedding of this group into the
endomorphism algebra of its Jacobian variety to determine if it is of GL(2
)-type.