HELP: Need work around for STORED PROCEDURE!

I have version 5.02.UC6 of the informix SE engine and am trying to convert some 4gl code to run in a stored procedure. I have only run into one problem so far and that is how do I subscript a character string. Example: DEFINE i INTEGER; DEFINE tmp1 CHAR(26); DEFINE tmp2 CHAR(1); LET i = 10; LET tmp1 = "HOW NOW BROWN COW."; LET tmp2 = tmp1[i]; -- Syntax error; LET tmp2 = tmp1[10]; -- NO Syntax error; Is is possible to subscript tmp1 in a general way with the variable i going from 1 to 26? By the way I have RTFM, but could not find a way. Thanks Peter peter@ems001.emsystem.com