Parser bug?

["Harald Hanche-Olsen" <hanche@imf.unit.no>]

; echo {a b <{c} d}
{%readfrom _devfd5 {c} {a b $_devfd5 d}}
; echo {a (b <{c} d)}
syntax error

Is there any good reason I cannot use parentheses here?  (I stumbled over
this in a longer script in which I did something of the form

some-command (-options -more options
  -yet more options
  <{some-other-command ...} )

Not a big deal - easy to work around - but can the grammar be tweaked to
accomodate this?

- Harald

(Weird - I keyed in the above, then forgot to send it before I went to
lunch - just to come back and find four other messages from the es list!
 Telepathy?  No - I don't believe it.)