Phone function gone when memory gets scarce

[Guest SGH-i620]

Me again...WM6 SGH-i620 here, but this is a device independent problem:

When I am using Opera Mobile and, say, open two or three big websites so that the memory gets scarce I sometimes experience a strange thing: the phone shows "no connection" (and no call is possible, too), but Internet (GPRS) still works fine.

Neither Hibernation nor stopping and starting the telephone function in connection manager helps. Only thing that helps is restarting the device.

I think I read something about the fact that sometimes a critical process that is responsible for telephony gets killed in low memory situations...but I can't find that thread any more.

Please, somebody experiencing the same sometimes, or someone knowing what to do? This makes my phone nearly unusable...