With a TYPE=LIST member you can specify parameters GROUP, IPNAME and IPPORT for transfers using TCP/IP. You can specify several IP-addresses as follows:
TYPE=LIST
IPNAME=111.111.111.111
IPNAME=222.222.222.222
If you want to specify different ports for these IP-addresses you need to specify them BEFORE the IPNAME; not behind.
TYPE=LIST
IPPORT=7500
IPNAME=111.111.111.111
IPPORT=9999
IPNAME=222.222.222.222
With this member specified in the SYSIN01 for the transfer XCOM tries to contact the partner XCOM Server on 111.111.111.111 at port 7500 and the partner XCOM on 222.222.222.222 on Port 9999.