Just to clarify, this can be done, but it requires editing a number of fields in the font to do it properly. Besides questions of doing this correctly, there are several issues. Most notably:
1) Most font licensing terms don't allow such modifications (Adobe's license being a notable exception).
2) Your modified fonts would then be incompatible with other people's versions. If you share your documents or collaborate, that could be an issue.
Cheers,
T