Qustions about psqlODBC 08.02

Hi.
  I have some questions with psqlodbc 08.02.0002 .
1> Is there only one driver installed by 08.02.0002 ? why?
   is it Unicode or ANSI ?
2> Is this driver thread safe ?
3> When I test the driver for ODBC Data Type by SQLColumns
   function , I found it return different value from 08.01.0200 .
   example:
              psqlodbc(08.02.0002)  psqlodbc(08.01.0200)
      char           -8              1
      char(1000)     -10             -1
      varchar        -9              12
      varchar(1000)  -10             -1
      text           -10             -10
      bytea          -3              -3
   why the return value changed ? where can I get the detailed change ?

If you could help me, that would be great!
thanks.

Regards,
zhao xin