SQL User Defined Function Issue

SQL Gurus,
   
  I did create a User Defined Function to call the LowerAdjust Prototype.
   
  I can update the FirstName by set FirstNme = LowerAdjust(FirstNme), shown 
below on Line 40.
   
  I need assistance,  to set a Returning value from a prototype to a host 
variable, as shown below in Line 35.
                                                             
                  C/exec sql                                             
0035.00      C+ set :Test3 =  LOWERADJUST(TEST3)                   
0036.00      C/end-exec                                             
0037.00                                                             
0038.00      C/exec sql                                             
0039.00      C+ Update TESTLIB/EMPLOYEE                             
0040.00      C+ set FirstNme = LOWERADJUST(FIRSTNME) with NC       
0041.00      C/end-exec                                             
0042.00   
   
  Compile Fails.
                                                  DIAGNOSTIC MESSAGES           
    
 MSG ID  SEV  RECORD  TEXT                                                      
 SQL0104  30      35  Position 35 Token TEST3 was not valid. Valid tokens: :.   
 .                

  Your hlep is greatly appreciated.