It looks like they have python setup you might be able to knock something up in python to send the mail then have your php just call the python function
example
python code:
#!/usr/bin/env python
import cgi
import smtplib
fields=cgi.FieldStorage()
print "Content-Type: text/html"#the mime header
print
print """
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>sender</title>
</head><body><center>"""
if 'message' in fields:
message=fields["message"].value
else:
message=None
if 'to' in fields:
to=fields["to"].value
else:
to=None
if bool(to)==True and bool(message)==True:
server = smtplib.SMTP('smtp.gmail.com')
server.set_debuglevel(1)
server.ehlo()
server.starttls()
server.ehlo()
#fill in those 3 fields then you can call like email.cgi?to=address&message=test
server.login("""~~~~~~~~gmailuser~~~~~~~""", "~~~~Gmail password~~~~~~~~~")
server.sendmail("~~~~from address~~~~~~~~~~", to, message)
try:
server.quit()
except:
pass
print"""
</body>
</html>"""