I want to store binary data in a BLOB field of a table (SUBTYPE BINARY)
with Firebird 2.0.3 on a Windows XP system. The BLOB data is real
binary data (no text) and will exceed the size of 32765 bytes
(available for VARCHAR fields/variables).

I want to be able to replace parts of the binary BLOB (for example
replace 4 Bytes at BLOB byte position 40000) on the Firebird server
side.

Does anybody know if there exists an UDF for that purpose? I know there
are functions to do that with text blob values up to the size of 32765
bytes, but that size is not sufficient in my case.

I want to do these replacement actions in the firebird server to hide
that stuff from the clients, to centralize these tasks on the server
and to avoid unnecessary network traffic between server and clients.

Thanks in advance.

Tia