[imp] Please help me!!!

[VJ.Srinivasan (JINIS)]

Hi All,
Greetings,
Thanks for your quick subscription.
Please help me.
I am using, 
qmail-toaster-1.03-1.0.9, 
vqadmin-toaster-2.3.4-1.0.6,
horde-toaster-2.2.3-1.0.5,
MySQL-server-4.0.12-0,
php-4.2.2-8.0.5,

Everything is working fine. Except, when I compose message from horde-toaster, this below error is throughing. 
What will be the solution. 
Thanks for your co-operation.

Fatal error: Call to undefined function: send() in /usr/share/toaster/htdocs/horde/imp/compose.php on line 860


Keep in >>>>>>>>>>>>>|<<<<<<<<<<<<<<< 
Thanks & Regards,
VJ. Srinivasan,
System Administrator,
Jin Information System (P) Ltd.,
401, Oxford House, 3rd Floor,
Rustom Bagh Main Road,
Off Airport Road, 
Bangalore, Karnataka,
India
Phone -- 91-80-5253001.

"You don't have to be great to start But 
You have to start to be great"