thread for sending messages from a database

Hi,
I use the version of kannel 1.1.6.
I am trying to make a thread that must do :
- querry a database
- send new messages (stored in the database)

In smsc_emi2.c I write a function that querries the database called
db_sender.
In smsc_emi2_create function I have started the thread right after the
receiver_thread
with the line 
gwthread_create(db_sender,conn);

when I start bearerbox, the thread starts and loops ok an he sends
messages.
The the problem is that when I receive a message, my thread (db_sender)
stops.

I send messages with function add_msg_cb(conn,msg).
Cann you tell me what is wrong?


Felly