SQL Developer

Dear developers,
I tried to run DBMSSTDX.SQL script since it is told that I had to run it before creating any procedure. When I execute it in SQL developer, it encounter some errors:
1. It complains the script try to create a package name "STANDARD", "DBMS_STANDARD", or "DEBUG_IO".
2. It complains the script try to change username and its password.

The following are the actual errors pasted from script output:
------------------------------------
ORA-06555: this name is currently reserved for use by user SYS
06555. 00000 - "this name is currently reserved for use by user SYS"
*Cause: You tried to create a package named "STANDARD",
"DBMS_STANDARD" or "DEBUG_IO". These are currently
reserved for use by user SYS.
*Action: Choose another name for your package.
create or replace public succeeded.

Error starting at line 209 in command:
grant execute on dbms_standard to public
Error report:
SQL Error: ORA-01031: insufficient privileges
01031. 00000 - "insufficient privileges"
*Cause: An attempt was made to change the current username or password
without the appropriate privilege. This error also occurs if
attempting to install a database without the necessary operating
system privileges.
When Trusted Oracle is configure in DBMS MAC, this error may occur
if the user was granted the necessary privilege at a higher label
than the current login.
*Action: Ask the database administrator to perform the operation or grant
the required privileges.
For Trusted Oracle users getting this error although granted the
the appropriate privilege at a higher label, ask the database
administrator to regrant the privilege at the appropriate label.
------------------------------------

Question:
Why the script giving me these errors?

Regards,
Valerie