Where can I find a complete list of predefined Oracle pl/SQL Exceptions?

These are for 11gr2, a quick scan says they are still the same:http://download.oracle.com/docs/cd/E11882_01/appdev.112/e10472/errors.htm#BABHDGGG

This is from $ORACLE_HOME/rdbms/admin/stdspec.sql (good point from egorius standard package is the place to look for the answer)

      /********** Predefined exceptions **********/  CURSOR_ALREADY_OPEN exception;    pragma EXCEPTION_INIT(CURSOR_ALREADY_OPEN, '-6511');  DUP_VAL_ON_INDEX exception;    pragma EXCEPTION_INIT(DUP_VAL_ON_INDEX, '-0001');  TIMEOUT_ON_RESOURCE exception;    pragma EXCEPTION_INIT(TIMEOUT_ON_RESOURCE, '-0051');  INVALID_CURSOR exception;    pragma EXCEPTION_INIT(INVALID_CURSOR, '-1001');  NOT_LOGGED_ON exception;    pragma EXCEPTION_INIT(NOT_LOGGED_ON, '-1012');  LOGIN_DENIED exception;    pragma EXCEPTION_INIT(LOGIN_DENIED, '-1017');  NO_DATA_FOUND exception;    pragma EXCEPTION_INIT(NO_DATA_FOUND, 100);  ZERO_DIVIDE exception;    pragma EXCEPTION_INIT(ZERO_DIVIDE, '-1476');  INVALID_NUMBER exception;    pragma EXCEPTION_INIT(INVALID_NUMBER, '-1722');  TOO_MANY_ROWS exception;    pragma EXCEPTION_INIT(TOO_MANY_ROWS, '-1422');  STORAGE_ERROR exception;    pragma EXCEPTION_INIT(STORAGE_ERROR, '-6500');  PROGRAM_ERROR exception;    pragma EXCEPTION_INIT(PROGRAM_ERROR, '-6501');  VALUE_ERROR exception;    pragma EXCEPTION_INIT(VALUE_ERROR, '-6502');  ACCESS_INTO_NULL exception;    pragma EXCEPTION_INIT(ACCESS_INTO_NULL, '-6530');  COLLECTION_IS_NULL exception;    pragma EXCEPTION_INIT(COLLECTION_IS_NULL , '-6531');  SUBSCRIPT_OUTSIDE_LIMIT exception;    pragma EXCEPTION_INIT(SUBSCRIPT_OUTSIDE_LIMIT,'-6532');  SUBSCRIPT_BEYOND_COUNT exception;    pragma EXCEPTION_INIT(SUBSCRIPT_BEYOND_COUNT ,'-6533');  -- exception for ref cursors  ROWTYPE_MISMATCH exception;  pragma EXCEPTION_INIT(ROWTYPE_MISMATCH, '-6504');  SYS_INVALID_ROWID  EXCEPTION;  PRAGMA EXCEPTION_INIT(SYS_INVALID_ROWID, '-1410');  -- The object instance i.e. SELF is null  SELF_IS_NULL exception;    pragma EXCEPTION_INIT(SELF_IS_NULL, '-30625');  CASE_NOT_FOUND exception;    pragma EXCEPTION_INIT(CASE_NOT_FOUND, '-6592');  -- Added for USERENV enhancement, bug 1622213.  USERENV_COMMITSCN_ERROR exception;    pragma EXCEPTION_INIT(USERENV_COMMITSCN_ERROR, '-1725');  -- Parallel and pipelined support  NO_DATA_NEEDED exception;    pragma EXCEPTION_INIT(NO_DATA_NEEDED, '-6548');  -- End of 8.2 parallel and pipelined support  /********** Add new exceptions here **********/

Predefined exceptions are declared in package SYS.STANDARD, there you'll surely find them all.

On my 9.2.0.7 I found one not in the list:

USERENV_COMMITSCN_ERROR exception;pragma EXCEPTION_INIT(USERENV_COMMITSCN_ERROR, '-1725');

In addition to your question: what is the name of exception, risen when ORA-03135: connection lost contact error appears. How can I handle it?

The solution is to define a new exception and associate it with an error code:

exception connection_error;pragma exception_init(connection_error, -3135);...exception    when connection_error then        ...

http://download-west.oracle.com/docs/cd/B19306_01/appdev.102/b14261/exceptioninit_pragma.htm