[Xy-pic] Problem with curved arrows to circular regions

[Bjarte M. Oestvold]

Hi

I've made an xymatrix where curved arrows go between circular regions.
The problem is that the arrows are slightly short, i.e., they do not
quite reach their target.  (Squares are no problem.)  Here's a minimal
example of the problem:

----------------------------------------------------------------------
\documentclass{article}
\usepackage[line,dvips,matrix,arrow,frame,curve]{xy}

\begin{document}
\newcommand{\cstate}[1]{*+++[F]\txt{#1}}

\xymatrix at +7ex{%
  *+++[F]\txt{AAAA} \ar@(dl,dr)[]_{b}
  }
\end{document}
----------------------------------------------------------------------


Did I misunderstand something? Or can I rewrite my code to avoid the
problem?  (I'm using Xy-pic version 3.7 <1999/02/16>.)

Sorry if this is a FAQ -- I tried to find an answer.  If I missed it a
pointer to a FAQ-answer will be appreciated.

Thanks in advance.

Regards,
  Bjarte

-- 
Bjarte M. Østvold       <bjarte at nr.no>          +47 22 85 26 22 (direct)
Norsk Regnesentral/Norwegian Computing Center   +47 22 85 25 00 (switchboard)
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