messaging.sms_send gave an "Already Sending" Error

[forumz]

S60 3rd with python s60 1.45.
I'm using messaging.sms_send to send a message, if the phone is happend out of signal(or in offline mode), the callback function showed the sending state stopped at EScheduledForSend, and never go to ESent or ESendFailed or other state. I waited for a while, and using messaging.sms_send again. It gave an "Already Sending" error, I can't send message with messaging.sms_send anymore. The only way to send out message again is to restart my program.

Is it possible to stop messaging.sms_send when it gave "Alread Sending" error after a certain period of time? So I can using it to send another message again without restarting my program.

[forumz]

I found this in Pys60 1.45 documents:

The optional parameter callback is invoked with the current status of the send operation as param-eter. The possible states are data items in the module messaging. Invoking another send while a previous send request is ongoing will result in RuntimeError being raised.
If the callback is not given, the sms send function will block until the message in the queue is either deleted or the sending has failed

Is there a way to delete the message in the queue?