Problem:
When passing a BLOb field which is over 8K in size through the ODBC driver 
(version 1.00.0809)  the contents are truncated. 

The error returned usually is as follows:
"contents truncated.."

Solution:
IB V4.x
Visigenic InterBase ODBC driver v1.00.0809

This is a bug in version 1.00.0809 of the Visigenic ODBC driver.  

Note: Bug is fixed in version V2.00.0902 of the Visigenic ODBC driver.

Note2:  BLOb is now truncated to 32k in the version 2.00.0902 Visigenic ODBC driver.