At first glance that looks OK to me. I have attached an example multi-part mime message that seems to work fine with your code. Check the messages that you are feeding in and see if they are really multi-part. 

From: Laura Rios <laura@oara.sf.ca.us>
To: steve@ntecom.za
Subject: Sara is two!
Mime-Version: 1.0
Content-Type: multipart/mixed; boundary="Snip snip snip"

Prologue: any text here is ignored by MIME mail programs 
--Snip snip snip
Content-Type: text/enriched; charset="us-ascii"

Hi, Steve.  Sara had her second birthday yesterday.  Can you believe i
+t?
She is so <bold>big</bold>!  Now if we can just live through the
"terrible twos" for a year, <italic>sigh</italic>.


Here are a few words from her.  I've also scanned in a picture of her
party.  Tell your boss thanks for letting us keep in touch by email.


Laura

--Snip snip snip
Content-type: audio/basic
Content-transfer-encoding: base64
Content-description: Sara says "I love you, Steve" (awww)

/Xr++/hoX2lqeXt8d/7z8/D5+PLw7/b+9fD09319/vz5f3j//Pz9fHp7fvrs9Wz/eH59d


/////////////////y8=

--Snip snip snip
Content-type: image/gif
Content-transfer-encoding: base64
Content-description: Cutting the cake, sort of

R0lGODdhQAHIAKMAAAAAAP+2bQAAACQAAAAASEgAAAAkSEgkJG0kJJEkAABIkZFIJCRttr
+Zt


l7Vry4B9aM+yKjifMosAADs=

--Snip snip snip--

----END----

[download]

In reply to Re: MIME to attach by steer
in thread MIME to attach by nathanvit

Title:
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