somebody put me into the right track. My SQL client seems to be too old.
When using IB_SQL created with IBObjects v. 4.8.7 my SP returns -60. I downloaded the last version of IB_SQL (which uses IBO v. 5.0.2) and the SP correctly returns 0. I have the solution of my problem now. This costed me several hours of work and frustration :( Thank you Peppe
