I have the same problem. In fact what it happens in my case is that the php script that should send the mail seems to be running forever whithout sending any output. If i stop the browser from loading the page generated it works... but otherwise it doesn't. I tried the php built-in mail() function, and also the PEAR sendmail implementation which opens a pipe to sendmail. The reult is the same in both cases. Actually if you try to run from the command-line something like:
/usr/sbin/sendmail -firstname.lastname@example.org -- email@example.com\n From: firstname.lastname@example.org\n
test mail body\n
you will see that sendmail doesn't quit and hangs up...
All tests above work perfect on linux but I need this also for a OSX machine
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