Pgadmin does not execute backup on table on tablespace

Hello,

Platform: Windows XP SP2
Language: English
Distribution: Binary Win32
Version: 1.6.3 rev:6112

When i try to execute backup on a table "MARC_FORMAT_TAGURI" wich is located
on tablespace "SIBI" i recieve this message:

Process returned exit code 1.
C:\Program Files\pgAdmin III\1.6\pg_dump.exe -i -h 192.168.1.1 -p 5432 -U
postgres -F p -D -v -f "C:\Documents and
Settings\Liviuss\Desktop\PostgresPort\MARC_FORMAT_TAGURI.sql" -t
"MARC_FORMAT_TAGURI" -n "SIBI" "TINREAD"
pg_dump: No matching schemas were found
pg_dump: *** aborted because of error

Process returned exit code 1.

Thanks,
Liviu