[OpenSER-Users] Strip Digits

I am sending an INVITE to Box A for "F+18007622265@boxa" Part of GW Table: gw_name grp_id ip_addr port uri_scheme transport strip prefix toll-free failover 5 XXXXXXXX /NULL/ /NULL/ /NULL/ 1 Part of LCR Table: id prefix from_uri grp_id priority 170 F+1800 5 1 This sends the call to box B XXXXXXXX per the GW table: Jan 29 04:03:16 boxb-sip /usr/local/sbin/openser[28118]: Req 41070 INVITE From <sip:asterisk@XXX.XXX.XXX.XXX> To <sip:F+18007622265@boxa> RURI <sip:+18007622265@boxb> It strips the F off in the RURI field but not in the TO field so boxb then fails the call as it doesn't know how to route a call to F+1800NXXXXXX. What can I do to make it re-format the to: field? The original problem I am trying to solve is that toll-free calls are routed to a system. If that system cannot handle the call I want that system to then place the call back to the OpenSER box (boxa) but instead of using the grp_id of 2 that +1800 calls would go to (and route to the system in question), I want to indicate that boxa should use group 5 and send the calls to boxb. There is probably a very easy way of doing this which doesn't involve a mangled dial string but I'm missing it so if anyone would like to assist me with this that would be great.