When you type a modem initialization command into the Windows XP HyperTerminal command window, you can only type the first character?
This behavior will occur if Hyper-Threading is enabled on your computer AND the AGERE SoftModem driver is installed.
To workaround this problem, turn off Hyper-Threading in your computer's BIOS, or get a real modem.
NOTE: For information about Hyper-Threading, see http://developer.intel.com/technology/hyperthread.
NOTE: Modem AT commands sent by a Telephony Application Programming Interface (TAPI) application work fine.