Polycom SIP 3.1 manual reg/ on page A-107, Note This may fail due to glare issues in which

			Configuration Files
	Permitted
Attribute	Values	Default	Interpretation
call.dialtoneTimeOut	Null, positive	60	Time in seconds to allow the dialtone to be
	integer		played before dropping the call.
			If set to 0, the call is not dropped.
			If set to Null, call dropped after 60 seconds.
call.lastCallReturnString	string of	*69	The string sent to the server when the user
	maximum		selects the “last call return” action.
	length 32
call.callsPerLineKey	1 to 24 OR	24 OR	For the SoundPoint IP 600, 601, and 650, the
	1 to 8	8	permitted range is 1 to 24 and the default is 24.
			For all other phones the permitted range is 1 to 8
			and the default is 8.
			This is the number of calls that may be active or
			on hold per line key on the phone.
			Note that this may be overridden by the
			per-registration attribute of
			reg.x.callsPerLineKey. Refer to Registration
			<reg/> on page A-107.
call.stickyAutoLineSeize	Null, 0, 1	0	If set to 1, makes the phone use "sticky" line
			seize behavior. This will help with features that
			need a second call object to work with. The
			phone will attempt to initiate a new outgoing call
			on the same SIP line that is currently in focus on
			the LCD (this was the behavior in SIP 1.6.5).
			If set to 0 or Null, the feature is disabled (this was
			the behavior in SIP 1.6.6).
			Note: This may fail due to glare issues in which
			case the phone may select a different available
			line for the call.
call.stickyAutoLineSeize.	Null, 0, 1	Null	If call.stickyAutoLineSeize is set to 1, this
onHookDialing			parameter has no effect. The regular
			stickyAutoLineSeize behavior is followed.
			If call.stickyAutoLineSeize is set to 0 or Null
			and this parameter is set to 1, this overrides the
			stickyAutoLineSeize behavior for hot dial only.
			(Any new call scenario seizes the next available
			line.)
			If call.stickyAutoLineSeize is set to 0 or Null
			and this parameter is set to 0 or Null, there is no
			difference between hot dial and new call
			scenarios.
			Note: A hot dial occurs on the line which is
			currently in the call appearance. Any new call
			scenario seizes the next available line.

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