This is  a permanent  restriction for  performance considerations.  It is
simply not  possible, in an interpreted  language like REXX, to  put full
RFC822  parsing code  everywhere it  would be  needed. The  incoming mail
parser properly splits the address, because it is a full parser, but when
the address  is manipulated  by lower-level  subroutines for  searches in
LIST files or  in XMAILER NAMES et  al, a PARSE instruction  is used. For
the  same reason,  blanks  are not  supported in  user  names, even  when
quoted. Other characters are no problem.
 
  Eric