I am trying to set streams_pool_size and I am getting an oracle error. Can somebody tell me what I need to do in order to fix this.

SQL> select * from v$version;

Oracle Database 10g Enterprise Edition Release - 64bi
PL/SQL Release - Production
CORE Production
TNS for Solaris: Version - Production
NLSRTL Version - Production

SQL> show sga

Total System Global Area 310378496 bytes
Fixed Size 1978272 bytes
Variable Size 197136480 bytes
Database Buffers 104857600 bytes
Redo Buffers 6406144 bytes
SQL> alter system set streams_pool_size = 50 m;
alter system set streams_pool_size = 50 m
ERROR at line 1:
ORA-02097: parameter cannot be modified because specified value is invalid
ORA-04033: Insufficient memory to grow pool