What would you do? The case of the unreachable telecommuter

Periodically, we ask three HR pros how they’d handle a difficult situation at work. Today’s problem: A manager’s having problems getting in contact with a telecommuting employee.
The Scene
Manager Betsy Reilly found HR manager Joe Paschen in his office poring over a giant stack of resumes.
“Joe, you work too hard,” said Betsy. “Let me interrupt you for a second.”
“Please do,” said Joe, rubbing his eyes. “I could use a break. What’s on your mind?”
“Well,” Betsy started, “I’m a little concerned about Steve Gennaro and the telecommuting arrangement we’ve set up with him.”
Joe thought for a second. “It wasn’t that long ago that we approved Steve to work from home a couple of days a week, right?”
“Right,” said Betsy. “And so far things have been pretty good. Except … “
“What?” asked Joe.
Betsy sighed. “There have been a couple of occasions in the past two weeks when Steve’s working from home where I just can’t get in touch with him. I call him, I email him – nothing.
“Eventually he gets back to me and we figure things out, but I’m stumped on what to make of it or what to do,” Betsy said.
“Why was he was out of touch?” asked Joe.
“He says he steps away from his desk momentarily,” Betsy said. “His argument is it’s no different than people stepping out for a smoke break or getting a breath of fresh air.
“But,” she continued, “sometimes I have questions that need to be answered right away. What am I going to do when I can’t get in contact with him when I really need him?”
If you were Joe, what would you say or do next?
What your peers had to say
An  HR manager in California
What she’d do: I’d tell Betsy she needs to talk with Steve and hammer out clear rules for days he works from home – for instance, that he’ll review any messages left for him within a set period of time.
Reason: More often than not, telecommuters are great employees you can trust. That doesn’t mean, however, that you can be lax about the arrangement. Working from home is a privilege, not a right.
An HR generalist in Nebraska
What she’d do: I’d call a meeting with Betsy and Steve to find ways to make sure Betsy can get in touch with Steve when there’s an emergency. Then we’d agree on a trial period for the solution – 30 or 60 days – and revisit things at that time to see if the solution is working.
Reason: We can’t rush to judgment. There was obviously a sound business reason we let Steve work from home in the first place, so we don’t want to simply erase that because of this small problem. Therefore, working to improve the relationship is the natural first step in this situation.
A director of HR in Maine
What he’d do: First, I’d make sure Betsy and Steve had set up as many ways as possible to get in contact with one another while Steve is working offsite.
Second, I’d suggest that Steve and Betsy agree to a typical structure for Steve’s day, whether that means he checks in with Betsy at specific times or he lets her know when he’s stepping out.
Reason: It doesn’t sound like there’s a formal telecommuting policy here, so that needs to be defined ASAP, keeping in mind what’s best for both Steve and the firm.