PROBLEM: Sendmail does not work or does not accept my optional arguments.
First make sure you have the correct path to sendmail which is /usr/sbin/sendmail
If you have the correct path, then you may need to know that sendmail is actually a symbolic link to another program called /usr/local/bin/mini_sendmail
Mini_sendmail accepts stdin and passes it on to an smtp server, behaving almost exactly like the real sendmail. The reason for using mini_sendmail is because you are inside a chrooted environment and you do not have access to the real sendmail. This type of circumstance was discussed publicly here.
Information about mini_sendmail can be obtained here or here.
Many times, what you are trying to do does not work because you are feeding options or flags to mini_sendmail that it does not understand like: -bm -f -oem -oi
Many times those options are unnecessary. Try just omitting them, calling mini_sendmail like this:
/usr/sbin/sendmail -t
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