Sendmail Install

All:

As is true every 4 months, I need to send a mail to around 500 people. The users are held in a MySQL database, easily accessible, and my preferred method of interaction is using PHP. I do not have Postfix correctly set up, PEAR Mail doesn't seem to work, and so I need to start from scratch.

My previous solutions have been inadequate at best, so I decided that I would install sendmail. I can find no trace of sendmail on my system, and have been trying to follow the instructions at http://sial.org/howto/sendmail/macosx/10.3-panther/

However, and although I have downloaded the newest version of Sendmail from sendmail.org, I do not seem to be able to get this installation to run correctly. I have performed the following steps:

1. Download and unzip tarball
2. navigate to folder and run sh Build

Below is an example of the feedback I am getting as this Build supposedly runs : it has been attempting to do so for some time, with no appreciable end in sight. I assume that I have done something incorrect, but what? Did I need to stop a Mail process of some type running beforehand?

/bin/sh: fork: Resource temporarily unavailable
/bin/sh: line 1: cd: libsmdb: No such file or directory
Making all in:
/sendmail.8.13.5/sendmail-8.13.1
/bin/sh: fork: Resource temporarily unavailable
/bin/sh: line 1: cd: sendmail: No such file or directory
Making all in:
/sendmail.8.13.5/sendmail-8.13.1
/bin/sh: fork: Resource temporarily unavailable
/bin/sh: line 1: cd: editmap: No such file or directory
Making all in:
/sendmail.8.13.5/sendmail-8.13.1
/bin/sh: fork: Resource temporarily unavailable
/bin/sh: line 1: cd: mail.local: No such file or directory
Making all in:
/sendmail.8.13.5/sendmail-8.13.1
/bin/sh: fork: Resource temporarily unavailable
/bin/sh: line 1: cd: mailstats: No such file or directory
Making all in:
/sendmail.8.13.5/sendmail-8.13.1
/bin/sh: fork: Resource temporarily unavailable
/bin/sh: line 1: cd: makemap: No such file or directory
Making all in:
/sendmail.8.13.5/sendmail-8.13.1
/bin/sh: fork: Resource temporarily unavailable
/bin/sh: line 1: cd: praliases: No such file or directory
Making all in:
/sendmail.8.13.5/sendmail-8.13.1
/bin/sh: fork: Resource temporarily unavailable
/bin/sh: line 1: cd: rmail: No such file or directory
Making all in:
/sendmail.8.13.5/sendmail-8.13.1
/bin/sh: fork: Resource temporarily unavailable
/bin/sh: line 1: cd: smrsh: No such file or directory
Making all in:
/sendmail.8.13.5/sendmail-8.13.1
/bin/sh: fork: Resource temporarily unavailable
/bin/sh: line 1: cd: vacation: No such file or directory

etc ....

any help will be most gratefully received

thanks, Oliver