Referring to FIGS. 4A and 4B, FIG. 4A is a perspective view of a handheld electronic apparatus 410 having a keyboard module similar to the keyboard module of FIG. 3 and FIG. 4B. is a top plain view of the handheld electronic apparatus of FIG. 4A. The handheld electronic apparatus 410 in the shown example is a PDA. However, it is understood by those skilled in the art that the handheld electronic a