diff --git a/doc/README.variables b/doc/README.variables
index cc5932fc148718edb9468eed03b4812508e81cf1..dfb6de3d10ea83f450d1a38fcf5c6a6698f3689f 100755
--- a/doc/README.variables
+++ b/doc/README.variables
@@ -52,6 +52,7 @@ ${ACCOUNTCODE} 	Account code (if specified)
 ${CALLERID}	Caller ID
 ${CALLERIDNAME}	Caller ID Name only
 ${CALLERIDNUM}	Caller ID Number only
+${CALLINGPRES}	PRI Caller ID presentation for incoming calls
 ${CHANNEL}	Current channel name
 ${CONTEXT}      Current context
 ${DATETIME}	Current date time in the format: YYYY-MM-DD_HH:MM:SS