Zend certified PHP/Magento developer

Successful Checkout redirects to empty cart but not using Redis

I am debugging a common problem that I have seen others asking about, losing user session data during a successful order which redirects to an empty cart.

Most solutions i have read about suggest a redis setting can fix that, by setting the following:

<break_after_frontend>5</break_after_frontend> 

However I have discovered that my site is using redis backend cache for config settings but not the redis session – in my Cm_RedisSession.xml I can see:

<active>false</active>

Further my local.xml does not have a redis_session node.

So my question – is there an equivalent set of settings for the out of the box session storage and a setting similar to ‘break_after_frontend’? I’ve been trying to fix this issue forever, finalyl felt as if I was on the home straight but it was a false dawn it seems!

Any ideas or suggestions welcome.