[gnome-db] blob (with postgresql)

i'm trying to use blob, with postgresql... but i have some problem,  
only with some files (for example pdf or tar.gz; while cvs and txt  
work; it doesn't seem to depend by file length)

the problem seems the loading into the db; in fact when i fetch the  
blob, it is trunked

i tried with the sample on libgda documentation

instead, with a simple program with postgresql native functions i can  
use blobs correctly

i tried to load the blob with libgda and fecth it with postgresql  
native functions and with php, but the result is the same: file trunked

i didn't recieve error from libgda

what could be the problem?

i'm using libgda 4.x.x from git

thanks in advance