[imp] problem with attached file

[jf]

Hello,

I have a problem (a bug)  when I send an e-mail with a at least 1,8Mb 
attached file.
The person whose the message is send have the link of the attached file, 
but when he clicks on it, the attached file is empty (0 Mb).

Meanwhile, when I write the e-mail, the attached file seems to be correct.

In php.ini , I configure that way :

file_uploads = On

upload_tmp_dir = /var/tmp

upload_max_filesize = 8M

I’ve apache 1.3
Php 4.1
IMP: 3.2.1
Horde: 2.2.1

Thanks