Meet-me conferencing services are provided by a software device (i.e. CallManager media streaming app) or a hardware conference bridge - not by the phones themselves...
The limits are set by the capabilities of the conference bridge - if you are using CM media streaming app, then the default maximum number of participants is 4, however you can increase this to up to 128 (in CM4.0) through the callmanager service parameters...
Aaron
Aaron
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