Is this a (Meridian) compiler bug?

[bonak@herky.cs.uiowa.edu (Esmail Bonakdarian)]

It the following subtype declaration (line 3) legal?  The LRM seems to
specify a type_mark after the 'is' reserved word (and an optional
constraint).
 
The Meridian compiler compiles this code without any problems though the
Telesoft compiler I have access to does not like it. I can fix the code by
changing line 3 to
 
subtype ROW_TYPE is INTEGER range 1 .. ROWS;
 
Am I reading the LRM incorrectly or have I stumbled across a bug in this
compiler? I would like somebody to confirm this for me before I contact
Meridian (by the way, do they have an e-mail address?).
 
Thanks.
 
Esmail
------------------
    Meridian AdaVantage v4.1  Source file: bug.ada  Page 1
    Sun Apr  7 1991 19:25:17
 
 
        1  procedure BUG is
        2
        3  ROWS: constant := 5;
        4
        5  subtype ROW_TYPE is 1 .. ROWS;
        6
        7  begin
        8    null;
        9  end;
 
    Compilation Summary
         Ada library used: ada.lib
         Compile options:
           (none)
         9 lines compiled.
         9 lines listed.
         No errors detected.
         No warnings reported.