Gaby,
I noticed that you are also converting LabVIEW 2.2 to LabVIEW 3.1 in another post. I would travel along that route and get your VI up to a more current version of LabVIEW.
Our support policy is to support the most current version of LabVIEW and one major revision back. At this time, we support LabVIEW 5.0 and later. You can purchase an upgrade to LabVIEW 6.1 for a minimal price. To do this, please go to http://www.ni.com/upgrade.
Randy Hoskin
Applications Engineer
National Instruments
http://www.ni.com/ask