ORA-01045: user lacks CREATE SESSION privilege; logon denied

[oracle@bogon ~]$ sqlplus  / as  sysdba

SQL*Plus: Release 10.2.0.1.0 - Production on Tue Jul 21 03:07:12 2009

Copyright (c) 1982, 2005, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup
ORACLE instance started.

Total System Global Area  301989888 bytes
Fixed Size                  1219088 bytes
Variable Size             104859120 bytes
Database Buffers          192937984 bytes
Redo Buffers                2973696 bytes
Database mounted.
Database opened.
SQL> create user MOMNPUP identified by MOMNPUP
  2  ;

User created.

SQL> grant RESOURCE to MOMNPUP;

Grant succeeded.

SQL> exit
Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options
[oracle@bogon ~]$ sqlplus MOMNPUP/MOMNPUP

SQL*Plus: Release 10.2.0.1.0 - Production on Tue Jul 21 03:10:09 2009

Copyright (c) 1982, 2005, Oracle.  All rights reserved.

ERROR:
ORA-01045: user MOMNPUP lacks CREATE SESSION privilege; logon denied


Enter user-name: system
Enter password:

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options

SQL>grant create session,resource to MOMNPUP;

Grant succeeded.

SQL> exit
Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options
[oracle@bogon ~]$ sqlplus  MOMNPUP/MOMNPUP

SQL*Plus: Release 10.2.0.1.0 - Production on Tue Jul 21 03:14:47 2009

Copyright (c) 1982, 2005, Oracle.  All rights reserved.


Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options

SQL>