[asterisk-users] Idiot's question

[Venefax]

I have two lines in my dialplan that I wish to make it into only one, and I
fail
X.,n(entrada),Set(CALLERID(num)=${CALLERID(num)}0000000000)
X.,n,Set(CALLERID(num)=${CALLERID(num):0:11})

It means: add '0000000000' to the caller id, and then take the first 11
chars from the left. It aims to detect null caller ids and replace them by
zeros. How can I write this expression in just one line?