11
I don't know, but I doubt that's the issue.
Stupid question I'm sure, but how did you do the upgrade? Did you:
1. delete the old module's files
2. upload the new files
3. update/refresh the module in module admin
Have you tried clearing the /templates_c directory (except for the index.html file?
All I can tell you is that v1.4 works on XOOPS 2.0.18.1 running on php5.
Sorry