Unable to allocate SGA_TARGET more than 2 GB on Oracle SPARC Solaris 11 running Oracle RDBMS 11.2.0.

 Hi,

 We are implementing Oracle RDBMS 11g R2 (11.2.0.3.0) for one of our clients on a new Oracle SPARC Solaris 11 (64-Bit) server. 

The sysadmin configured the Server referring to Note:Requirements To Install Oracle 11gR2 RDBMS On Solaris 11 SPARC / X86_64 [ID 1496618.1].

 I installed Oracle RDBMS 11gR2(11.2.0.3.) s/w but during Database creation using DBCA, I was not able to allocate more than 2 GB Memory for SGA. So I set the SGA to 2 GB and completed the Database Creation. Database is working fine. But when I want to increase the SGA_TARGET to more than 2 GB I get this message:

SQL> startup nomount;