[gnome-db] crash after blob saved

i'm using libgda 5.2.4 and postgresql 9.4.4

i have a strange behavior: after saving a blob using gda as the  
example in documentation, every gda connection operation, for example  
gda_connection_new_from_string or  
gda_connection_execute_non_select_command, crashes without i found a  
reason

instead it works using lo_import and simply update the oid field

what could it be?

thanks in advance