store procedure - parameter passing

when calling a store procedure, do I have to pass the exact length of
the inpur parm?
 
Using the following procedure as an example
CREATE PROCEDURE AILSEQMSP        
(                                 
     In    inSerialNo    Char(15),
     In    inOffice      Char(3), 
     In    InSystem      Dec(1,0),
     Out   outErrFlag    Dec(1,0),
     Out   outErrCode    Char(7), 
     Out   TotalRecords  Dec(8,0) 
)                                 
Result Sets 1           
Language RPGLE          
External name AILSEQMRP 

would the following different call statement make a different?
- call AILSEQMSP('A              ', '   ', 1, rsParm1, rsParm2, rsParm3)
- call AILSEQMSP('A', ' ', 1, rsParm1, rsParm2, rsParm3)
- call AILSEQMSP('A  ', '', 1, rsParm1, rsParm2, rsParm3)
 
thanks.