Another option named page alert is now functional in firmware 1.7.5. What it does, it takes telephone number and ring it for 15 seconds, then hangs up. It is efficient way to inform you about urgent alerts along with SMS, or as separate alert. But it is meant only for high importance alerts, since it needs to wait for GSM modem to dial, ring and hang up. It is processed at last in alerting thread, but stop processing of alerts for long time, especially when there are more then one telephone number to page/call.

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