getting a call back after you've already worked for the company is a good sign.
we (
Web design Internet development, Ireland - email marketing, content management systems, email response systems) sometimes have people in for work experience. Apart from my own hiring, only one other person has ever been asked to take a permanent position here based on that, as in the time he was working as a temp here, he proved that he could handle the work. (that's not a hint to potential temps not to come to us - if you can handle what we do, then you will do well here)
as for "negotiable"... who knows!