The OT/PPP Read me states the following:
"Using Global Village PC Card Products
The Global Village software included with your modem adds an entry to the "Connect via" pop-up menu of the Modem control panel called "PowerPort PC Card". Under some circumstances, an entry for the actual slot your PC Card is plugged into will show up as well ("Upper-slot," "Lower-slot"). These slot-specific items should not be used and the "PowerPort PC Card" item should be used instead or the port will be erroneously reported as busy."
This is not correct. The "port busy" message is not generated by selecting the wrong slot, it is generated in low-memory conditions because of a bug in the Open Transport software. Global Village has a fix for this at their web site, here is the URL:
http://www.globalvillag.com
This article was published in the 9 Jun 1997 "Information Alley".