Leading space in amount value passed to PayFlowPro (and possibly other processors) causing invalid amount error

See this forum post for description and a fix for PayflowPro.php :

http://forum.civicrm.org/index.php/topic,29198.msg126421.html#msg126421

However, I would recommend doing a bit more digging to see why an untrimmed value is being passed into $params['amount'] - especially seems there some indication in the forum post that this is specific to membership-related contribution payments. Might be a better fix to trim the value earlier in the flow.