[SM-PLUGINS] CentOS5-CentOS6 Migration problem: html_mail issue - HTML-Formatted email in Squirrelmail disappears (details below ...)

[Max P. <py...@br...>]

Greetings,

Recently, due to a disk failure I made a quick decision to move our site 
to a new machine running a fresh installation of CentOS 6 from a degrading 
machine that was built on CentOS 5.

Since this was sudden, enough issues developed, but we've managed to 
resolve a number of them. One that is still outstanding relates to 
squirrelmail's html_plugin


In Squirrelmail, you can install a plugin called html_mail that allows you to 
compose html-formatted email.

This plugin functions with Firefox and Internet Explorer; it doesn't function 
in Google Chrome.

In CentOS 5 with PHP5.1 using html_mail, I would toggle the HTML source button. 
Then, I could copy and paste  html-formatted text with complicated html 
(tables, css, etc) from a text editor into the the html-formatting pane of 
squirrelmail, and the message would be delivered as html-formatted to the 
recipients.

In CentOS 6, with PHP5.3, using Squirrelmail with the html_mail plugin, using 
this same procedure (toggle html source to bring up "text mode" in the 
composition pane) and copying html-formatted text from a text editor into the 
html-window in Squirrelmail, the delivered email only shows the header 
information.

Using pine, I see that there is an attachment, viewing the attachment, I see 
the original html code that was composed in a text editor.

Viewing this same received email in a web-based client (Gmail or Squirrelmail), 
all of html-formatted part disappears.

Looking at a part of a CentOS 5 mail header where this process was successful, 
I see:
Content-Length: 132323
Lines: 3332
Parts/Attachments:
    1.1   OK     1,169 lines  Text (charset: ISO-8859-1)
    1.2 Shown    2,137 lines  Text (charset: ISO-8859-1)
    2   Shown        5 lines  Text

Looking at a part of a CentOS 6 mail header where this process is failing, I 
see:
Parts/Attachments:
    1.1   OK     1,898 lines  Text (charset: ISO-8859-1)
    1.2 Shown        1 lines  Text (charset: ISO-8859-1)
    2   Shown        5 lines  Text

It's the "1.2" part

Finally, looking at the message in the "Sent" folder, the html-formatted 
message disappears.

In many issues that have related to this migration the primary reason has 
been changes in PHP 5.3 differing from PHP 5.1's functionality. This 
html_mail issue may or may not relate to that.

In addition, we're using sendmail as the MTA (with the hope of moving to 
Postfix, which is stock in CentOS 6), since our legacy setup used 
sendmail.

The sendmail version we used on CentOS 5 was 8.13.8-8.el5; now it is 
8.14.4-8.

Recognizing that there are a myriad of points involved but also having 
reviewed some of the squirrelmail-plugin archives and seeing that 
versions of this problem have been reported, would there be any 
suggestions on how to troubleshoot and resolve this?

Much thanks.

Max Pyziur
py...@br...