Init Siemens mc35i not always the same

[Matisoft]

When I start up my application, I can see the init of the modem in a terminal window.

Sometime I get: +CPMS: "SM",0,20,"MT",25,45,"MT",25,45
Sometime I get: +CPMS: "MT",25,45,"MT",25,45,"MT",25,45

When I get the first kind of init, the application don't work correct OnSmsReceived() triggers.
How I can force the modem to start always with:  +CPMS: "MT",25,45,"MT",25,45,"MT",25,45

Regards
Marcel Timmerman