You could also send one of those pager out calls to another vm box. Set the other box to take a message and do pager notfifications as well.
I have a question, what is the application? Is this an after hours service person on call? I never endorse having only one person responsible to respond. Sometimes pagers are out of service area, or the paging system is down. If the person has a manager, or other responsible person, I would add them to the notification after a given amount of time. They can then get a hold of someone via other avenues than the pager.
The place I used to work had one person on call for on site response, all others in the rotation were notified after an interval as well. The others had to call the person that was supposed to go on site, if he did not answer the pager. If they could not contact him, then they had to respond. It went down the list of everyone qualified, and included management to respond if all else failed.
You do not always get what you pay for, but you never get what you do not pay for.