[OSL | CCIE_Voice] IPMA - Shared line?

When would one want to use shared line instead of proxy line configuration with IPMA? What are the advantages/disadvantages? Cliff

[OSL | CCIE_Voice] IPMA shared line mode problem can anybody help on that?

Hi, I configured shared line mode with IPMA. in IPMA configuration section of MANAGER user, when I click update ,I get Error updating device and line(s) information.Service Parameters not configured .You must configure IPMA device configuration default and softkey templates service parameters