Thank you for answering Helen and mick...!

Adding the commit ^ after excection creation and thus before the
procedure create statement seemed to do the trick.

I also checked the file with command prompts edit, because editing
with windows notepad can sometimes add something really odd
characters to the script files and thus cause errors when compiling
them to the database with isql tool.

But the problem is now solved and the new 1.5.1 Firebird seems to be
working just fine :)

MariJo