actually, that would depend on what your script does.
If the given webserver deliberately doesnt have mail() enabled, and your script does not obtain information on using a separate SMTP server or something, then emailing would be impractical.
On the other hand, if the user required an email facility in the first place, it shouldnt be too difficult to use that to email.
You will have to determine a point of installation where this can be done, e.g. when the database is setup.