Compaq Armada M700 Series Reference Manual page 200

The equipment shall be set to ensure that calls are answered
between 3 and 30 seconds of receipt of ringing (S0 set between 2
and 10). This ensures:
a. A person calling your modem will hear a short burst of
ringing before the modem answers. This confirms that the
call has been successfully switched through the network.
b. Caller identification (which occurs between the first and
second ring cadences) is not destroyed.
This equipment does not fully meet Telecom's impedance
requirements. Performance limitations may occur when used in
conjuction with some parts of the network. Telecom will accept
no responsibility should difficulties arise in such circumstances.
This equipment should not be used under any circumstances
which may constitute a nuisance to other Telecom customers.
This equipment shall not be set to make automatic calls to the
Telecom '111' Emergency Service.
Regulatory Notices B-13