[imp] Random attachment problems

[Babita]

Horde: 3.1.4
Imp: H3 (4.1.4)
PHP Version: 4.4.1
OpenBSD 4.1

Hello.

We're seeing two major problems on our system related to attachments and 
we're having a difficult time isolating the cause.

1. uploading certain file types (eg .java and .vms) causes the composition 
screen to go blank.

.vms fails on all browsers except IE 7.0
.java fails on Safari 2.0.4 but succeeds on Firefox 1.5 (on machine A)
.java fails on Firefox but succeeds on IE (on machine B)

2. sometimes the file does not attach despite the "successfully attached" 
message confirmation (ie, the file does not show up in the recipient's 
email).

.jpeg has inconsistent results on both Safari and Firefox
.jpg and .gif are successfully received every time

These files are no more than 1.5MB in size and do not exceed any upload 
limits. All front end machines have a common NFS mounted upload directory. 
We recently upgraded from Horde 3.1.2 and Imp 4.1.2, applying patches 
incrementally to get to the latest stable release. None of these problems 
existed on the old system.

Any help is appreciated.

--
Babita Rana
AICT
University of Alberta