Hi,
I didn't use LS1010 before and don't know the answer of your question. But basically I can say that any ATM swith is NOT a MPLS enabled ATM switch. An ATM switch must run IP protocol to operate as an MPLS enabled ATM swicht. Pure ATM swicthes can't do it. On the cell mode operation ATM switch builds a control PVC (default 0/32) and over this PVC it creates LDP session to other equipment. So the software should also support this type of operation.
Regards