I have a problem with a UDF lib that I have written myself and am
looking for help.

The UDF lib implements a small C function that I use in an update
trigger. This seems to work fine on most PCs.
However, trying the software on some computers, I ran across two
(among 30+) computers where the application would encounter problems
and Firebird quits.
The firebird.log contains:
--------------------------
DEMRN1145 (Server) Fri Aug 19 12:01:41 2005
DirectoryList: unknown parameter 'Full
C:\Programme\Firebird\Firebird_1_5\UDF\ProPXUDF.dll', defaulting to None

DEMRN1145 (Server) Fri Aug 19 12:03:18 2005
DirectoryList: unknown parameter 'Full UDF\ProPXUDF.dll', defaulting
to None

DEMRN1145 (Server) Fri Aug 19 12:05:09 2005
The user defined function: PROPXFORMATVAL
referencing entrypoint: ProPXFormatVal
in module: ProPXUDF.dll
caused the fatal exception: Access violation.
The code attempted to access a virtual
address without privilege to do so.
This exception will cause the Firebird server
to terminate abnormally.

DEMRN1145 (Server) Fri Aug 19 12:05:09 2005
Access violation.
The code attempted to access a virtual
address without privilege to do so.
This exception will cause the Firebird server
to terminate abnormally.
--------------------------

I don't understand the first two -> what are they for?
The other two refer to my UDF lib and it looks like an access
violation which causes Firebird to quit.

I have turned my code upside down to find the error. Nothing. In
contrast, it seems my function returns ok and then Firebird crashes.

As because the code works fine on the vast majority of the systems, is
there perhaps something wrong with the FB installation on the systems
that failed? What should I be looking for?

Any help would be appreciated....