SQLExecute returns empty SQLState and SQLMsg

Hi,

When I use BindParameter() to bind a BLOB type value and restart the PG server before SQLExecute().
The SQLExecute() returns -1 expectedly, but the SQLState and SQLMsg return empty values unexpectedly.
--------------------------------
   SQLState: 00000
   SQLMSG: (empty)
--------------------------------

[To Reproduce]
    Client                      Server
1. SQLConnect()
2. BindParameter()
3.                              restart PG
4. SQLExecute()

I also tried to bind the other types, they all return correctly.
--------------------------------
   SQLState: HY000
   SQLMSG: The connection has been lost;Error while preparing parameters
--------------------------------

I didn't find any explain about this problem in psqlodbc's document.
If this is a bug, could anyone give me some suggestions to solve or avoid this problem?

Any help would be appreciated!

Regards,
Fengzh