[Exim] Exim and /etc/resolv.conf as a symlink to /etc/ppp/re…

Hi. I'm using Exim as an SMTP with a dial-up connection on Linux
2.2.16. I started testing the option 'usepeerdns' of pppd(8) that
writes up to two nameservers on /etc/ppp/resolv.conf. Since I'm not
using any ip-up scripts, I decided to make a symlink to
/etc/resolv.conf.

The problem is that Exim (and maybe other applications and servers, I
don't know) don't seems to like resolv.conf being a symlink, and
when I send a message it fails. The solution was to reverse it,
/etc/ppp/resolv.conf being the symlink.

Is there any reason to ignore /etc/resolv.conf when it's a symlink?
Do other applications fail?

Thanks.