I've recently seen users encounter problems when trying to use a cell phone to connect to an ISP or a RAS server after upgrading from Windows 9x to Windows XP. When you use a cell phone keypad to dial the number and make a connection, you can hear the tones and you know that the server is responding. However, you can't use DUN to make the same connection through an XP PC. I discovered that the problem is the dashes between the groups of numbers (i.e., between the area code, exchange, and last four digits). If you eliminate the dashes, you can connect.
—Paul Haviland
havilandp@volpe.dot.gov