Build issues on RHEL4 with PCRE

[Simon Matter]

Hi,

While doing some work on our cyrus-imapd RPMs I found that 2.4.4 will not
build on RHEL4 because of PCRE being too old.
Configure checks for pcreposix.h but that's not enough because REG_UTF8 is
not defined in older PCRE. This worked well with 2.3.16 because it did
care for the case where PCRE was there but no REG_UTF8.

Can anyone suggest a good solution? (Note, we can not simply update PCRE
because we should use the version shipped with the OS).

Regards,
Simon