I made the changes that the message you referred me to indicated. Here are the resulting settings:
[root@smeserver ~]# db configuration show php
php=service
AllowUrlFopen=Off
PostMaxSize=40M
UploadMaxFileSize=40M
status=enabled
[root@smeserver ~]#
Unfortunately, it still doesn't work. What happens now is that the web gui will only allow files of less than 10MB in size to be attached, but it will allow multiple files of less that 10MB to be attached for a total of more than 10MB. However, when I hit the send button the page crashes. A dialog box comes up asking about viewing non-secure pages, and when I say yes, I just get a message saying the page could not be displayed. The email isn't sent, and it's not in the draft folder either, when I log back in.
Now, I can send large attachments through outlook using IMAP, so some of the settings are effective in that situation.
mudtoe