How to bypass silent to remind calendar event ?

Hi,

I have missed too many events.

I have events on my calendar, but if the iphone is on silent mode (button on the left switced to red).

I just want to know if there is a way to have calendar event that ring even if we are in silent mode... just like alarm on the clock.

Could we do that ? How - parmeters, applications ... ?. I don"t want to jailbreak my iphone.

Thanks for your help.