Sending SUBSCRIBE from Asterisk


I’m using Asterisk as a “probe” to test the quality of a VoiceMail system. I have developped a java application that controls an Asterisk through asterisk-java. It calls the Voicemail system to leave messages and then retrieve those messages.
The aim is to detect problems on the VoiceMail system and measure its performance. This all works fine.

But now I would like to test the MWI function of the VoiceMail system. What I need is to have my Asterisk server send a SUBSCRIBE and then leave a message and wait for the NOTIFY. And that’s where I get into trouble : I don’t know how I can get Asterisk to send a SUBSCRIBE. I’m not even sure that it is possible. It seems that Asterisk was made to receive SUBSCRIBE messages, but not send them?

Does anybody have an idea?

Thanks a lot.