[GENERAL] Another Regular Expression "Problem"

I've got a CGI frontend that I'd like to give users the ability to type in regular expressions into forms and do queries based up this data. During testing things work fine as long as I keep with simple expressions like:

   select "first", "last" from "employees" where "first" ~ '^Charles'

But if I do something like the following, I get nothing:

   select "first", "last" from "employees" where "first" ~ '^(Charles)|(James)'

I looked down in src/backend/regex at re_format.7 and this is explained in that document as "extended" RE's. I've tried this RE with egrep and it matches lines like I want (pretty simple stuff here). What gives?
--
Charles Curley, Staff Engineer
Computer Integrated Manufacturing
Lockheed Martin Ocala Operations