use SOAP::Lite +trace => [ fault => \&log_faults ];

sub log_faults {
        open LOGFILE, ">soap_trace.txt";
        print LOGFILE $_[0] . "\n";
        close LOGFILE;
}

Subroutine SOAP::Trace::fault redefined at
        C:/strawberry/perl/site/lib/SOAP/Lite.pm line 2254 (#1)
    (W redefine) You redefined a subroutine.  To suppress this warning, say

        {
        no warnings 'redefine';
        eval "sub name { ... }";
        }