I have a Definity V11 and have been reading up on implementing EC500. I've got it working, and it's pretty cool. My question is about all these XMOBILE extensions needed to support this. Avaya says to assign 2 extensions for every office phone if you want to be able to get multiple calls to your call, and 4 extensions if you want to include your home phones also. They suggest using similar extension numbers for the XMOBILE's, such as keeping the last 2 digits the same. Does anyone know why that's important? Obviously this software can be a big drain on a dialplan, so why is it important to bounce around assigning these seemingly meaningless extensions? I'd rather assign them sequentially, just to use the dialplan more economically. If I need to figure out what someone's XM extensions are, I could just do a List Usage Ext or List Xmobile Mapping command right? Maybe I'm missing something. Is there any reason the user would need to know his XM extensions?