Is U[sub e3] Really Related to the Solar Neutrino Solutions?

It is important to measure U[sub e3] in the lepton flavor mixing matrix in order to understand the structure of Majorana neutrino mass matrix. Recently it is conjectured that the measurement of U[sub e3] would discriminate one solution among various solar neutrino ones provided that the three mass eigenvalues of neutrinos have the relation m[sub 1]≪m[sub 2]≪m[sub 3] or m[sub 1]∼m[sub 2]≪m[sub 3]. In this letter we show that this conjecture is rather restrictive and the relation [formula] is derived by a nontrivial assumption and U[sub e3] cannot discriminate among solar neutrino oscillation solutions without the information on another physical parameter. [formula available in full text]. [ABSTRACT FROM AUTHOR]