Control destination extensions of call waiting caller id?

I’m on Asterisk 1.4, have a digium TDM410 with a pair of FXOs and a pair of FXSs.

I have VoicePulse voip service and a pair of voip phone numbers. Inbound calls for each of the 2 numbers are directed towards specific fxs stations.

I just discovered that call waiting caller id is going to all fxs stations regardless of the inbound number.

How can I configure so that call waiting caller id is only sent to the desired station based upon the inbound number?