I can't attach a file due to the IMP2.2.5

rage rage@wces.tc.edu.tw
Tue, 26 Jun 2001 14:36:15 +0800 

 Hi,all:
   I've upgraded the imp's version to imp-2.2.5+horde-1.2.5. It works very
well except I can't attach any files.
   I've checked the /tmp's permission being 777. What can I do, and how to
fix the problem.
   My OS is FreeBSD ver.3.1, and http server is
apache-1.3.20+php-4.0.5+mysql-3.22.27.

  Thanks