tcpserver Global Vars:
SPF_ACTION (control/spfaction)
SPF_TARPIT (control/spftarpit)
SPF_TARPIT_TIME (control/spftarpittime)
SPF_EXPLAIN_STATE (control/spfexplainstate)
SPF_TRUSTED_STATE (control/spftrustedstate)
SPF_GUESS_STATE (control/spfguesstate)
SPF_HEADER_STATE (control/spfheaderstate)
By setting these in your environment with appropriate values you can nicely alter the behaviour of libSPF for an individual person or groups of people on your network. A great example is by placing SPF_ACTION inside of tcp.smtp and setting it to a 0 for 127.0.0.1.
127.:allow,RELAYCLIENT="",RBLSMTPD="",SPF_ACTION="0"
This way 127.0.0.1 never has SPF checks performed on them. I'm sure you get the idea.