socket connection through sap pi(single stack)

Hi experts,

My client has the requirement in which sap pi needs to establish tcp/ip connection with the third party vendor.

the flow is :

from sap ecc ...> sap pi(single stack)......>3rd party

earlier it was

sap ecc...........>jco...................>3rd party through socket programming

now they want to replace jco with sap pi  but the problem is 3rd party can only accept the data through sockets[please note that scenerio is asyn]..

I have read the following link:

Socket Integration with XI

but wasnt able to understand much (beacuse of my little understanding )

I have also read that seeburger is the another option but my client is not willing to spend a single penny .

so is there any other solution..?

pls suggest....

thanks in anticipatiom