Using the SQL GRANT statement for EXECUTE on a Stored Procedure

The following doesn't function from either Ops Nav or ISQL like it does
in the rest of IBM's DB2s:

GRANT EXECUTE ON SEL220SP1 TO PUBLIC;

and ISQL Prompting for GRANT EXECUTE says, in essence,  "What the hell
is that statement?"  I only know SELECT, INSERT, UPDATE, etc.,  when its
clearly in the SQL Reference manual.

In Run SQL Scripts I get:

GRANT EXECUTE ON SEL220CLSP TO PUBLIC;

SQL State: 42601
Vendor Code: -104
Message: [SQL0104] Token EXECUTE was not valid. Valid tokens: DELETE
INDEX INSERT SELECT UPDATE REFERENCES ALTER. Cause . . . . . :   A
syntax error was detected at token EXECUTE.   yada, yada, yada

Is this an IBM DB2 or just a name-only?  

What gives?

Thanks,

Dave Odom