A note on new sources of gaugino masses

In IIB orientifold models, the singlet twisted moduli appear in the tree-level gauge kinetic function. They might be responsible for generating gaugino masses if they acquire non–vanishing F-terms. We discuss some aspects of this new possibility, such as the size of gaugino masses and their non-universalities. A possible brane setting is presented to illustrate the usefulness of these new sources.