SNMP TRAPS BY ETH0 AND PPP

Hello,
I have an application with SNMP and I use two ETH0 and PPP1 (modem gsm) interfaces.
Since both interfaces I can consult and sets.
But I have a problem because only traps receipt for ETH0 and not by PPP.
I would like to receive traps both ways how do I can do? Can the GSM network traps eats?
Thank you.