Often, but not always, calendar alarms on my Sprint Treo 650 will hang the Treo (whether I clear them or not). Result is when I try to power on it takes several seconds to come on, and it won't let me disable keyguard so I'm locked out, requiring soft reset. Alternately, it won't power on at all.

If I don't discover the problem for a while, it will drain the battery.

Some days I soft reset 2-5 times a day. Plus, I miss the crash-causing alerts altogether (defeating the purpose of the alarm).

I have turned mine in for a new/refurbished 650. Still happens.
I have done a hard reset and not added any add-on software. Still happens.
I have tried using Sprint network time and NOT using network time (read in a different thread). Did not solve it.
I absolutely can not operate without calendar alarms.

Is there any solution to this?

Thank you.