The way to do this is enable the DHCP Service on each CCM. Then split your pool between them. And home half your phones to each, that way it always works.
CCM1 - 192.168.1.0 - 192.168.1.128
CCM2 - 192.168.1.129 - 192.168.1.254.
This way you always have working DHCP.
HTH, please rate useful posts.
Chad