We have been using PHPJabbers scripts since 2011 when we bought the Property Listing script. It has been running without a glitch since then and just this last month we purchased the Bus reservations script. We are very happy with the script and the support we receive. Every question is answered promptly and all issues sorted out and I have to point out these issues were not script related but they still helped us resolve it every time.
I can definitely recommend using PHPjabbers.