postgresql-8.2-504.jdbc4.jar and backslash

Hello.
I use this jar driver for connection to postgresql 8.2.3-1 in Windows XP.
In my database I use UFT8 codepage.
I need to save some filepath in some character varying(255) field in table1.
That path looks like this: f:\temp
in String class like this: "f:\\temp";
I try to execute following SQL statement:
UPDATE "table1" SET "field1"='f:\\temp'
in String object it looks like: "UPDATE \"table1\" SET \"field1\"='f:\\temp'".
After statement executed I get on SELECT folowing:
f:<tab symbol>emp

Why? There were two back slashes!!!
When I try to execute that update statement in pgAdminIII everything is OK!!!

Please, help me to decide this problem. How can I save filepath with backslashes?