I copied the following declaration for Hoefler Text, and it works. However
when I tried it for other Fonts (e.g., Warnock Pro), it does not work:
\DeclareFontShape{U}{warnock}{m}{sc}%
{<-> "Warnock\space Pro:Letter\space Case=Small\space Caps"}{}
Please let me know if I am doing things right.
Atip