Just thinking off the top of my head, you could try monitoring for a file. For example, make a simple text file on the share you want to monitor called monitor.txt, and then monitor for the existance of that file. You could also make the test time very short, like 10 seconds or so. If the share is not accessible in whatever time you decide, the monitor would fail.
This is admittedly a work around for what would be an awesome monitor to have, but it should at least get the share monitored for you.
Does anyone know if there is a way within ipmonitor v9 to view the availability of remote shares?
Does the drive space monitor, using "RPC" communications type, not meet your needs?
Remember: If there isn't any trust between the two boxes, you may need to add an identical account to both machines and use a "Windows credential" on the ipMonitor box. The account on the ipMonitor box will need to be able to login locally.
I'll give the monitoring for the existance of a file a try, that sounds like it good workaround.