Okay all sorted !!!
So i'm now using my Google Apps Imap account with a cron job to collect the emails!!!
As far as I can see you cannot simply run the /api/cron.php in a browser.
What you need to do is enter your account details in the email account setup page.
Then make sure you tick "Enable POP/IMAP email fetch"
Make sure in the general settings that "Enable cron call on staff's activity" is unselected.
Then go to Settings / API and put 127.0.0.1 in the New Ip box
Type three random words in the Phrase box
and then click ADD
Doing that will generate you a hashed code in the top API Key section of the page.
COPY THAT HASH!!!!!
Okay all good so far!!
Now I'm using Ubuntu 9.10 and have already installed webmin to manage it.
So in webmin I go to Scheduled Cron Jobs create a new one with the settings
execute job as = nobody
make it active
Then thanks to the post http://osticket.com/forums/showthread.php?t=3158(http://osticket.com/forums/showthread.php?t=3158)
Add the command as
wget -q -O /dev/null --user-agent=RE4A05834506BAA1AAC51C748058294C http://localhost/osTicket/api/cron.php(http://localhost/osTicket/api/cron.php)
REPLACING your path to cron.php and the RE4A05834506BAA1AAC51C748058294C with you hash that you just copied in the API KEY section.
Then set the times you want it to run at and then SAVE it
Thats it, Job Done!