SRND at http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_implementation_design_guide_chapter09186a00806375f2.html#wp1044818

in the section:

Deploying Variable-Length On-Net Dial Plans with Partitioned Addressing

and the subsection within it:

Inter-Site Calls Within a Cluster:

translation_pt 91212555.1xxx to be translated to 1xxx

and another sub-section

Outgoing PSTN and IP WAN Calls:

LD RP: 9.1[2-9]xx[2-9]xxxxxx

If you look at these two, there seem to be a big problem with this solution in the case IP wan goes down, the IP phones in the HQ where CCM exist are not able to call the remote office 2125551xxx through pstn because call always will look for 91212555.1xxx and translate to 4 digits but they are unregistered already and should went into SRST mode. But the call manager can not route the call at all unless there is a feature allows CCM to do this if the phone is down and it will detect it and route to pstn? Is this a new feature in CCM 5.x?