Thanks to the work and post by Syrex I have been able to get a workable PPTP connection.
What I have done on my DD-WRT router is add the following to the startup window.
Found here - Administration > Commands > Startup
echo 'noaccomp' >> /tmp/pptpd/options.pptpd
I have verified that it works both over 3G and from another WiFi network connection
I did it this way so all I will need to do is remove command from the startup window if a real fix is released.
Thanks again Syrex