Can't send SMS. Everything else works fine

[freakadelic]

Hi all,

My phone is an iPAQ 614c and for some reason I can't send SMS (text) messages.
Everything else works fine. I can email, internet, send and receive MMS, receive SMS and telephone.

Sms messages stay in the outbox and after about 10 minutes I receive an error message that the message could not be sent. I already checked the sms service number of my provider, which is correct.
If I put my SIM in another phone, I can send SMSs, so I guess it has nothing to do with my provider blocking me from sending.

Flashing the ROM from WM6.0 to WM6.1 did not change anything.

Anyone else with this problem? Or, even better, with a solution?

[freakadelic]

I have run some tests and it turns out that the sms remains in the outbox until I phone someone. As soon as the other person picks up the phone (i.e. a connection is established) the sms message is sent out...
Hence, it appears that the sms program in WM6.1 won't send unless there is a phone conversation going on. I haven't found any solution for this on the internet. Anyone came across this problem before?