Version:           1.13.5 (using KDE 4.5.1) 
OS:                Linux

If you are inline-forwarding a message with attachment and you select a different identity, Composer replaces the message text with the raw original message (Boundary, Content-Transfer-Encoding, base64-encoded attachment). The original attachment stays too.

Reproducible: Always

Steps to Reproduce:
1. Have two identities: Foo and Bar.
2. Receive an email with attachment for Foo.
3. Right-click it, Forward -> Inline. Composer opens. Original message text is surrounded by "---- Forwarded message ----", that's right. The attachment is shown in the Attachments panel below the message, that's right.
4. In the Identity listbox (above the message) select Bar.
5. The attachment is still shown in the Attachments panel below, that's right.
6. The message text now contains raw email text (that's wrong!), like this:

--Boundary-00=_eRUQNR6a5ZV38m0
Content-Type: text/plain;
  charset="us-ascii"
Content-Transfer-Encoding: 7bit
-----------------------------------------
[[Original text goes here.]]

--Boundary-00=_eRUQNR6a5ZV38m0
Content-Type: application/msword; name="H1B Checklist - client.doc"
Content-Disposition: attachment; filename="H1B Checklist - client.doc"
Content-Transfer-Encoding: base64
X-Attachment-Id: 4640c48084a4685a_0.1

[[Base64-encoded attachment goes here]]

Actual Results:  
Raw message content (including some email headers, base64-encoded attachments) is displayed in Message text field.

Expected Results:  
Only message text should be displayed in Composer, not headers, boundaries or attachments.

If you switch the Identity back to Foo, the text stays cluttered.