[imp] attaching unknown filetypes

[Paul A Sand]

Hi --

I may well be missing something easy here, but..

We recently upgraded to Horde 3; we're currently running 3.0.4, and Imp
H3 (4.0.3). We're running on dual-Opteron boxes under Red Hat Enterprise
Linux 4 with their provided RPMs for Apache, PHP, sendmail, etc. We're
running UW IMAP.

Not sure it matters, but test.php saith, among other things:

    MIME Magic Support (fileinfo): No
    MIME Magic Support (mime_magic): Yes

All is going pretty well for most folks, but one of our faculty
users reports that he and his students are having trouble attaching his
"TreeAge" files (with a .tre file suffix) to mail messages with Imp.

(Not that it matters, but TreeAge is decision analysis software: 
http://www.treeage.com/)

Specifically: the file selection dialog works OK, the attach button
works in that the user sees "Added <file> as an attachment" afterwards,
but hitting "Send message" does not actually send the message; the
compose window remains in place.

The only thing I can find in the logs is from imapd:

    Command stream end of file, while reading line

There's no *general* problem with attachments; as near as I can tell,
people can attach .doc, .xls, .mov, etc. files just fine. As a test,
I renamed the test file.tre file provided to file.mov, and that worked.
(But I'd rather not offer that as a workaround.)

The files are typically small, maybe a few thousand bytes.

So I get the feeling that maybe my problem lies in "unrecognized" file 
suffixes on attachments. Testing this by renaming the file to file.glg
seemed to confirm that; it didn't work either.

So: Is there a workaround or fix to this problem that I'm
just not seeing?  (I've tried looking in the list archive, but
nothing pops out at me.  The closest recent thing I saw was here:
http://marc.theaimsgroup.com/?l=imp&m=111272298123593&w=2 
...  but that user
reported a problem with *all* attachments, and that's emphatically not
the problem here.)

-- 
-- Paul A. Sand                 | This is really the future I
-- University of New Hampshire  | wanted. Although I expected
-- pas at unh.edu                  | longer battery life.
-- http://pubpages.unh.edu/~pas |     (James Lileks)