A help with a regular expresion and HMR to Change SDP Owner "o" information

Hi fellows.

I was trying to do a HMR to get the IP information in the second via in a INVITE  and when I make a test-sip-manipulation I have the messages that uri-host can not be used like when you use for a FROM/TO/Contact, etc

For the Via that are my invite suppose I have the following.

Via: SIP/2.0/UDP 172.1.1.1:5060;branch=z9hG4bKhei1fb304gnhhhgl71k0.1

Via: SIP/2.0/UDP 172.2.2.2:5060;branch=z9hG4bKabf1244d1006db72

I was trying to define this and get the error (could not be parsed as a URI)

header-rule

        name                           via_hr

        header-name                    Via[1]