p5.12-svn-simple : Warning: SVN::Core missing or outdated - installation fails

[dan@…]

I'm running command:

sudo port install git-core +svn

This fails with error:

Error: org.macports.configure for port p5.12-svn-simple returned: configure failure: command execution failed
Error: Failed to install p5.12-svn-simple
Please see the log file for port p5.12-svn-simple for details:
    /opt/local/var/macports/logs/_opt_local_var_macports_sources_rsync.macports.org_release_ports_perl_p5-svn-simple/p5.12-svn-simple/main.log
Error: The following dependencies were not installed: p5.12-svn-simple

looking at the log file, it seems following is root cause:

===> Warning: SVN::Core missing or outdated.

Version of SVN which is installed is: svn, version 1.7.5 (r1336830)

I am running OSX Lion 10.7.4 having upgraded from Snow Leopard with an earlier version of MacPorts installed

I have followed instructions at ​https://trac.macports.org/wiki/Migration

I have attempted to implement several fixes suggested in response to other tickets to rectify similar sounding issues - but none have worked (sorry - I did not keep a list of every fix I've tried :-\)